Crystal structures of bis[1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S,N,O)cobalt(III)-tetra(thiocyanato-κN) cobalt(II) methanol solvate, bis{1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S,N,O}nickel(II) bis(thiocyanate) and (1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S,N,O)bis(thiocyanato-κN)zinc(II) European Journal of Chemistry 13 (2) (2022) 196-205 European Journal of Chemistry ISSN 2153-2249 (Print) / ISSN 2153-2257 (Online) – Copyright © 2022 The Authors – Atlanta Publishing House LLC – Printed in the USA. This work is published and licensed by Atlanta Publishing House LLC – CC BY NC – Some Rights Reserved. https://dx.doi.org/10.5155/eurjchem.13.2.196-205.2253 European Journal of Chemistry View Journal Online View Article Online Crystal structures of bis[1-(1-hydroxypropan-2-ylidene)thiosemicarbazide- κ3S,N,O)cobalt(III)-tetra(thiocyanato-κN) cobalt(II) methanol solvate, bis{1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S,N,O}nickel(II) bis(thiocyanate) and (1-(1-hydroxypropan-2-ylidene)thiosemicarbazide- κ3S,N,O)bis(thiocyanato-κN)zinc(II) Cheikh Ndoye 1, Gregory Excoffier 2, Gorgui Awa Seck 1, Ousmane Diouf 1, Ibrahima Elhadji Thiam 1, Mamadou Sidibé 2 and Mohamed Gaye 1,* 1 Department of Chemistry, Faculty of Sciences and Technology, University Cheikh Anta Diop, Dakar, 10700, Sénégal 2 Spectropole, Fédération des Sciences Chimiques de Marseille, Aix-Marseille Université, Marseille, 13397, France * Corresponding author at: Department of Chemistry, Faculty of Sciences and Technology, University Cheikh Anta Diop, Dakar, 10700, Sénégal. e-mail: mohamedl.gaye@ucad.edu.sn (M. Gaye). 10.5155/eurjchem.13.2.196-205.2253 Received: 09 March 2022 Received in revised form: 08 April 2022 Accepted: 26 April 2022 Published online: 30 June 2022 Printed: 30 June 2022 The reactions of Schiff base 1-(1-hydroxypropan-2-ylidene)thiosemicarbazide (H2L), with salt of thiocyanate metal (II) (Co, Ni, or Zn), provided one dinuclear and two new mononuclear complexes, formulated respectively as {[Co(LH)2]2·[Co(NCS)4] ·2(MeOH)} (1), {[Ni(H2L)2]·[(NCS)2]} (2) and [Zn(H2L)(NCS)2] (3). These compounds have been studied and characterized by elemental analysis, infrared, and ultraviolet-visible (UV-vis) spectroscopies. The structures of the three complexes have been resolved by X-ray crystallography technique. The dinuclear complex 1 crystallizes in the orthorhombic space group Fdd2 with the following unit cell parameters a = 33.1524 (3) Å, b = 19.3780 (2) Å, c = 13.2533 (2) Å, V = 8514.28 (17) Å3, Z = 16, R1 = 0.025 and wR2 = 0.063, the mononuclear complex 2 crystallizes in the monoclinic space group P21/n with the following unit cell parameters a = 11.5752 (1) Å, b = 12.3253 (1) Å, c = 14.2257 (2) Å, β = 106.855 (1)°, V = 1942 (4) Å3, Z = 4, R1 = 0.038 and wR2 = 0.106 and the mononuclear complex 3 crystallizes in the monoclinic space group P21/c with the following unit cell parameters a = 6.1121 (2) Å, b = 26.8272 (7) Å, c = 8.0292 (2) Å, β = 99.876 (3)°, V = 1297.04 (6) Å3, Z = 4, R1 = 0.026 and wR2 = 0.057. The asymmetric unit of Complex 1 contains one cationic unit in which the ligand acts in its monodeprotonated form in tridentate fashion and one half of the anionic unit containing two thiocyanate co-ligands. In complexes 2 and 3, the ligand acts in its neutral form in a tridentate manner. In complex 2, two ligand molecules coordinate the Ni(II) center, and the thiocyanate moieties remains uncoordinated. In complex 3, the Zn(II) is coordinated by one ligand molecule and two thiocyanate groups through their nitrogen atoms. Numerous hydrogen bonds consolidated the structures of complexes 1, 2, and 3 in a three-dimensional network. Complex Schiff base Octahedral Thiocyanate X-ray diffraction Square pyramidal Cite this: Eur. J. Chem. 2022, 13(2), 196-205 Journal website: www.eurjchem.com 1. Introduction The Schiff bases formed from the condensation reaction between thiosemicarbazide and a carbonyl compound are widely studied in organic chemistry and coordination chemistry. In fact, thiosemicarbazide and its derivatives have interesting biological properties [1-3]. Organic molecules obtained from thiosemicarbazide which have shown anti- oxidant [4,5], antitumor [5,6], antituberculosis [7,8], antifungal [7,9], antibacterial [7,10] or analgesic [11] properties are largely reported in the literature. To improve the properties of these derivatives, many metals transition [12-14] and tin complexes [15-17] were prepared from these types of Schiff bases. In addition to the important biological properties observed, physical properties [18,19] are discovered owing to the presence of a metallic center in the molecular structures formed. The original structures of these compounds induce physical properties such as magnetism [20-22], fluorescence [23-25] or catalytic [26-28] in lanthanides and transition metals complexes. Detailed studies of the molecular structures and mode of coordination of these Schiff bases are carried out. The thiosemicarbazide moiety can complex in various ways. Indeed, a thione/thiol equilibrium can be established. Thus, the sulfur atom can bind to the metal in its thione form or in its thiolate form [29-31]. There are also complexes in which the sulfur atom remains uncoordinated [32,33]. In this article, we report the synthesis and structural characterization of the Co(II/III), Ni(II) and Zn(II) complexes of 1-(1-hydroxypropan- 2-ylidene)thiosemicarbazide (H2L) (Scheme 1). ABSTRACT RESEARCH ARTICLE KEYWORDS https://dx.doi.org/10.5155/eurjchem.13.2.196-205.2253 https://www.eurjchem.com/ https://dx.doi.org/10.5155/eurjchem.13.2.196-205.2253 mailto:mohamedl.gaye@ucad.edu.sn http://www.eurjchem.com/ https://crossmark.crossref.org/dialog/?doi=10.5155/eurjchem.13.2.196-205.2253&domain=pdf&date_stamp=2022-06-30 Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 197 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 Scheme 1. Synthetic scheme for the preparation of H2L and complexes. 2. Experimental 2.1. Materials and instrumentation Thiosemicarbazide, 1-hydroxyacetone, potassium thiocya- nate, cobalt nitrate hexahydrate, nickel nitrate hexahydrate and zinc nitrate hexahydrate were purchased from Sigma-Aldrich and used as received without further purification. All solvents used were of reagent grade. Melting points were determined on a Büchi 570 melting-point apparatus and were uncorrected. Elemental analyses of C, H, and N were recorded on a VxRio EL Instrument. Infrared spectra were obtained on an FTIR Spect- rum Two of the Perkin Elmer spectrometer in the 4000-400 cm- 1 region. UV-vis spectra were recorded using a PerkinElmer Lambda UV-vis spectrophotometer. The 1H and 13C NMR spectra of the Schiff bases were recorded in DMSO-d6 on a BRUKER 500 MHz spectrometer at room temperature using TMS as internal reference. 2.2. Synthesis of ligand 1-(1-hydroxypropan-2-ylidene) thiosemicarbazide (H2L) The compound H2L is synthesized using the method reported by Netalkar et al. [34] with a slight modification. In a 250 mL flask containing 30 mL of methanol, 16.460 mmol (1.5 g) was introduced. A methanol solution containing 16.460 mmol (1.130 mL) of 1-hydroxyacetone was added and the mixture was refluxed for 4 hours. On cooling, the beige solution gives a white precipitate, which is recovered by filtration, washed with 2×20 mL of methanol, then 20 ml of diethyl ether, and dried in a desiccator. 1-(1-Hydroxypropan-2-ylidene)thiosemicarbazide (H2L): Color: White. Yield: 80 %. M.p.: 175-176 °C. FT-IR (KBr, ν, cm-1): 3428 (OH), 3379 (NH2), 3218, 3164 (N-H), 1660 (C=N), 1259 (C=S), 1068 (C-O). 1H NMR (500 MHz, DMSO-d6, δ, ppm): 10.01 (s, 1H, NH), 7.90, 8.06 (s, 2H, NH2), 4.88 (s, 1H, OH), 4.01 (s, 2H, -CH2-OH), 1.87 (S, 3H, -CH3). 13CNMR (125 MHz, DMSO-d6, δ, ppm): 14.15 (-CH3), 65.36 (-CH2-OH), 153.08 (C=N), 179.54 (C=S). Anal. calc. for C4H9N3OS: C, 32.64; H, 6.16; N, 28.55. Found: C, 32.61; H, 6.14; N, 28.51%. UV-Vis (λmax, nm): 277 2.3. Synthesis of complexes 1, 2, and 3 In a 50 mL round bottomed flask, 0.6793 mmol of H2L, were dissolved in 10 mL of methanol. 20 mL of methanol containing 0.6793 mmol of cobalt nitrate hexahydrate and 2.7172 mmol of potassium thiocyanate was filtered and added to the above solution (for the nickel complex 0.6793 mmol of the ligand H2L, 0.3396 mmol of nickel nitrate hexahydrate and 0.6793 mmol of potassium thiocyanate were used; for the zinc complex 0.6793 mmol of H2L, 0.6793 mmol of zinc nitrate hexahydrate and 1.3586 mmol of potassium thiocyanate were used). The resulting solution was refluxed for 2 hours before being filtered. The filtrates were left to slow evaporation. After a week, orange crystals for cobalt (1), green for nickel (2) and colorless for zinc complex (3) were recovered. Bis[1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S, N, O) cobalt(III)-tetra(thiocyanato-κN)cobalt(II) methanol solvate (1): Color: Orange. Yield: 55 %. FT-IR (KBr, ν, cm-1): 3438, 3371 198 Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 Table 1. Crystal data and structure refinement for compounds 1, 2, and 3. Compound 1 2 3 Empirical formula C22H40Co3N16O6S8 C10H18N8NiO2S4 C6H9N5OS3Zn Formula weight 1057.98 469.27 328.73 Temperature (K) 295(2) 295(2) 295(2) Crystal system Orthorhombic Monoclinic Monoclinic Space group Fdd2 P21/n P21/c a, (Å) 33.1524(3) 11.57520(10) 6.1121(2) b, (Å) 19.3780(2) 12.32530(10) 26.8272(7) c, (Å) 13.2533(2) 14.2257(2) 8.0292(2) α (°) 90 90 90 β (°) 90 106.8550(10) 99.876(3) γ (°) 90 90 90 Volume (Å3) 8514.28(17) 1942.36(4) 1297.04(6) Z 8 4 4 ρcalc (g/cm3) 1.651 1.605 1.683 μ (mm-1) 1.604 5.672 2.363 F(000) 4328.0 968.0 664.0 Crystal size (mm3) 0.32 × 0.18 × 0.06 0.36 × 0.2 × 0.2 0.1 × 0.1 × 0.1 Radiation MoKα (λ = 0.71073) CuKα (λ = 1.54184) MoKα (λ = 0.71073) 2Θ range for data collection (°) 3.92 to 58.232 8.708 to 145.628 5.37 to 59.162 Index ranges -45 ≤ h ≤ 45 -25 ≤ k ≤ 25 -18 ≤ l ≤ 17 -12 ≤ h ≤ 14 -14 ≤ k ≤ 15 -17 ≤ l ≤ 17 -7 ≤ h ≤ 8 -36 ≤ k ≤ 36 -11 ≤ l ≤ 10 Reflections collected 73314 16439 28641 Independent reflections 5395 [Rint = 0.0338, Rsigma = 0.0136] 3814 [Rint = 0.0348, Rsigma = 0.0269] 3372 [Rint = 0.0250, Rsigma = 0.0142] Data/restraints/parameters 5395/1/253 3814/6/234 3372/0/181 Goodness-of-fit on F2 1.048 1.027 1.097 Final R indexes [I≥2σ (I)] R1 = 0.0253, wR2 = 0.0615 R1 = 0.0378, wR2 = 0.1023 R1 = 0.0258, wR2 = 0.0546 Final R indexes [all data] R1 = 0.0278, wR2 = 0.0633 R1 = 0.0402, wR2 = 0.1061 R1 = 0.0321, wR2 = 0.0571 Largest diff. peak/hole (e.Å-3) 0.58/-0.33 0.54/-0.45 0.33/-0.31 Table 2. Selected bond lengths for complexes 1, 2, and 3. Complex 1 Complex 2 Complex 3 Atom Atom Length(Å) Atom Atom Length(Å) Atom Atom Length(Å) Co1 N1 1.887(2) Ni1 N4 2.0018(15) Zn1 S1 2.4335(5) Co1 N4 1.892(2) Ni1 N1 2.0057(15) Zn1 O1 2.1846(16) Co1 O2 1.989(2) Ni1 O2 2.1234(14) Zn1 N1 2.0973(15) Co1 O1 2.013(2) Ni1 O1 2.1240(14) Zn1 N4 1.9576(16) Co1 S1 2.1818(8) Ni1 S2 2.3867(5) Zn1 N5 1.9743(18) Co1 S2 2.1843(8) Ni1 S1 2.3983(5) S1 C4 1.6959(18) Co2 N8 1.942(4) S1 C4 1.698(2) S3 C6 1.634(2) Co2 N7i 1.955(4) S2 C8 1.695(2) S2 C5 1.622(2) S2 C4 1.735(3) N2 C4 1.344(3) N4 C5 1.144(2) S3 C10 1.610(4) N5 C8 1.344(3) N5 C6 1.148(2) Symmetry code:(i) -x+1, -y, z. (OH), 3331 (NH2), 2065, 2014 (SCN), 1640 (C=N), 1224 (C=S), 1049 (C-O). Anal. calc. for C22H40Co3N16O6S8: C, 24.98; H, 3.81; N, 21.18. Found: C, 24.95; H, 3.79; N, 21.13%. UV-Vis (λmax, nm): 267, 280, 530. Bis{1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S, N, O}nickel(II)bis(thiocyanate) (2): Color: Green. Yield: 62 %. FT- IR (KBr, ν, cm-1): 3378 (OH), 3252 (NH2), 3159 (N-H), 2039 (SCN), 1660 (C=N), 1259 (C=S), 1049 (C-O). Anal. calc. for C10H18N8O2S4Ni: C, 25.60; H, 3.87; N, 23.88. Found: C, 25.56; H, 3.86; N, 23.85%. UV-Vis (λmax, nm): 277, 483, 816. (1-(1-Hydroxypropan-2-ylidene)thiosemicarbazide-κ3S, N, O) bis(thiocyanato-κN)zinc(II) (3): Color: Colorless. Yield: 74 %. FT-IR (KBr, ν, cm-1): 3357 (OH), 3265 (NH2), 3170, (N-H), 2100 (SCN), 1660 (C=N), 1259 (C=S), 1052 (C-O). Anal. calc. for C6H9N5OS3Zn: C, 21.92; H, 2.76; N, 21.30. Found: C, 21.90; H, 2.74; N, 21.21%. UV-Vis (λmax, nm): 280. 2.4. X-ray data collection, structure determination, and refinement Single crystals of 1, 2 and 3 were grown by slow evapo- ration of methanol solution of the corresponding complex. Suitable crystals were selected and mounted on a Rigaku Oxford Diffraction SuperNova diffractometer at the MoKα radiation for compounds 1 and 3 and at the CuKα radiation for compound 2. The crystals were kept at 295(2) K during data collection. Details of the X-ray crystal structure solution and refinement are given in Table 1. Using Olex2 [35], the structure was solved with the SHELXT [36] structure solution program using direct methods and refined with the SHELXL [37] refinement package. The crystallographic details of compounds 1, 2 and 3 are summarized in Table 1, and the bond lengths, bond angles of compounds 1, 2 and 3 are listed in Tables 2 and 3, respectively. 3. Results and discussion 3.1. General study The H2L ligand is synthesized according to the procedure of Scheme 1. It is obtained in the form of a pure white powder with a yield of 80% and a melting point of 175-176 °C. The compound was characterized by spectroscopic methods such as FTIR and 1H and 13C NMR. The FTIR spectrum gives several characteristic bands. The broad band at 3428 cm-1 indicates the presence of a hydroxy group in the molecule. The bands at 3379 and 3218 cm- 1 are attributed to antisymmetric vibration and symmetric vibration of the -NH2 amino group [38]. The band at 3164 cm-1 is due to the elongation of the N-H bond of the hydrazinyl group [39]. The band due to the C=N moiety is pointed at 1660 cm-1 while the characteristic bands due to the thioamide NH-C=S moieties are pointed at 1259 and 795 cm-1. The absence of the band characteristic of the S-H, expected at ca. 2600 cm-1, indicates that the compound is only in its thione form. The 1H NMR spectrum of the ligand shows a broad signal characteristic of the OH group at δ 4.88 ppm. The signals at δ 7.90 and 8.06 ppm are, respectively, attributed to the two protons of the -NH2 group. The signal at δ 10.01 ppm is due to the -NH proton. Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 199 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 Table 3. Selected bond angles for complexes 1, 2, and 3. Complex 1 Complex 2 Complex 3 Atom Atom Atom Angle (°) Atom Atom Atom Angle (°) Atom Atom Atom Angle (°) N1 Co1 N4 176.71(9) N4 Ni1 N1 169.08(6) O1 Zn1 S1 150.09(5) N1 Co1 O2 95.41(9) N4 Ni1 O1 93.25(6) N4 Zn1 S1 100.55(5) N4 Co1 O1 96.30(9) N1 Ni1 O1 77.71(6) N4 C5 S2 179.14(18) O2 Co1 S1 168.55(6) O2 Ni1 S2 161.09(4) C5 N4 Zn1 169.45(18) S1 Co1 S2 90.80(3) O1 Ni1 S2 95.78(4) N4 Zn1 N1 135.67(7) N8 Co2 N8i 110.5(3) N4 Ni1 S1 104.76(5) N5 Zn1 S1 104.52(6) N8i Co2 N7i 107.24(17) O1 Ni1 S1 160.09(4) N4 Zn1 N5 114.48(8) N8 Co2 N7 107.24(17) S2 Ni1 S1 94.74(2) N5 Zn1 N1 107.54(7) N7 C10 S3 179.2(4) N7 C9 S3 179.6(2) N5 C6 S3 178.31(19) N8 C11 S4 178.1(4) N8 C10 S4 176.1(2) C6 N5 Zn1 168.74(18) Symmetry code:(i) -x+1, -y, z. Figure 1. Single crystal structure of complex 1. Two singlet signals at δ 4.01 and 1.87 ppm are also observed, attributed to the -CH2- and -CH3 groups, respectively. Two characteristic signals from the azomethine (C=N) and thiocarbonyl (C=S) carbon atoms are pointed at δ 153.08 and 179.54 ppm, respectively in the 13C NMR spectrum. The complexes were synthesized using a 1:2:1 molar ratio of M(NO3)2.6H2O, (M = Co, Ni, or Zn), KNCS and H2L in MeOH solution under reflux. Upon coordination of the ligand to the metal ions, the infrared spectra of the resulting complexes 2 and 3 still show bands attributed to the -NH2, -NH- and -OH groups with small shifts. This observation shows that the ligand acts in its neutral form in these two complexes. However, for complex 1, the band due to hydrazinyl -NH disappeared from the spectrum. The ligand acts in its mono deprotonated form. In addition, a band pointed at 3438 cm-1 is indicative of the presence of an -OH group. For all three complexes, the bands due to the azomethine group undergo a strong displacement. The complex 2 shows a C=N band at 1610 cm-1 and a C=S bands at 1225 cm-1 and 759 cm-1, while complex 3 exhibits bands at 1604 cm-1 for C=N and bands at 1248 cm-1 and 755 cm-1 for C=S. For complex 1, the C=N band is pointed at 1640 cm-1 and the bands characteristic of C-S are pointed at 1224 and 741 cm-1. The shifts of these bands compared to the bands of the free ligand indicate that the nitrogen atom of the azomethine and the sulfur atom of the thiocarbonyl are involved in the coordination of the metal in complexes 1, 2, and 3. The sharp intense band observed in the ligand spectrum at 1068 cm-1 and attributed to the C-O single bond in the free ligand undergoes a 16-19 cm-1 shift to lower frequencies in the spectra of the complexes. This fact is indicative of the involvement of the oxygen atom of the alcohol function in the coordination. Thus, it is observed that in all the complexes the ligand acts as a tridentate ligand through the sulfur atom of the thioamide function, the nitrogen atom of the azomethine function and the oxygen atom of the alcoholic function. The amino and hydrazinyl nitrogen atoms remain uncoordinated. For all the complexes, the presence of thiocyanate groups is observed. The infrared spectrum of complex 1 gives two bands pointed at 2065 and 2014 cm-1. The duplication of these bands suggests the presence of two non-equivalent thiocyanate groups [40]. The IR spectra of complexes 2 and 3 show a band attributed to the thiocyanate group at 2100 and 2039 cm-1, respectively. The position of the bands shows non-coordination or coordination of the thiocyanate group through the nitrogen atom [41-43]. In the electronic spectrum of the ligand, an intense band at 277 nm is attributed to the intraligand n → π* transition associated with the C=N and C=S groups. This band is observed in all complexes with a variation of λmax from 0 to 3 nm. The UV-visible spectrum of complex 1 shows another band at 267 nm, which is due to a π → π* transition in the S=C=N- thiocyanate moiety. The crystal field theory of low spin octahedral Co(III) complex predicted two spin allowed d-d transitions, namely 1A1g→1T1g and 1A1g→1T2g. The electronic spectrum of complex 1 showed a band as a shoulder at 530 nm assigned to one of the two expected transitions [44]. Ni(II) complex 2 gives two other bands at 480 nm and 816 nm. In the case of Ni(II) complex, three transitions 3A2g→3T2g(F) (ν1), 3A2g→3T1g(F) (ν2), and 3A2g→3T1g(P) (ν3) are predicted [45]. The band at 483 nm can be attributed to the transition 3A2g→3T1g(F) (ν2) while the band at 816 nm is attributed to the transition 3A2g→3T2g(F) (ν1) [46,47]. 3.2. Description of the structures 3.2.1. Complex 1 The compound 1 crystallizes in the orthorhombic system with the space group Fdd2. The selected bond distances and angles relevant to the coordination sphere of the complex are given in Tables 2 and 3, respectively. The ORTEP representation of the complex 1 formulated as {[Co(LH)2]2·[Co(NCS)4]· 2(MeOH)} is shown in Figure 1. The cobalt(II) center of the anionic unit formed by the tetrathiocyanatecobalt moiety is located on the crystallographic two fold axis of the Fdd2 space group and accounts for only ½ in the asymmetric unit. Thus, the asymmetric unit contains 0.5 tetrathiocyanatocobalt moiety, one Co(III) ion, two mononegative ligands (HL-), and one uncoordinated methanol molecule. The Co(III) ion is coor- dinated by two mono-deprotonated ligand which act in tridentate fashion, yielding a hexacoordinated metal ion. Each ligand molecule is coordinated to the Co(III) cation through one alcoholic oxygen atom, one azomethine nitrogen atom, and one sulfur atom. The N2O2S2 environment around Co(III) is best described as a distorted octahedral geometry, the basal plane being occupied by O1, N1, S2, and N4. 200 Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 Table 4. Hydrogen-bond geometry (Å, °) for complex 1. D H A D-H H···A D-A ∠D-H···A O1 H1 N2i 0.85 1.81 2.643(3) 165.9 N6 H6B O3 0.86 2.07 2.915(5) 166.7 N3 H3A S3ii 0.92 2.81 3.646(3) 152.4 N3 H3B O1iii 0.85 2.61 3.109(4) 118.7 C3 H3E S1iii 0.96 2.86 3.740(4) 153.7 O3 H3 S3 0.89 2.51 3.348(3) 158.6 O3 H3 N3iv 0.89 2.70 3.122(4) 110.8 C7 H7A S4 0.96 3.02 3.769(3) 136.2 C7 H7C S2i 0.96 2.88 3.801(4) 160.4 O2 H2 N5iii 0.92 1.82 2.715(3) 162.0 C5 H5B O3iii 0.97 2.54 3.253(4) 130.6 C9 H9A N2v 0.96 2.55 3.474(6) 161.8 Symmetry codes: (i) -x+5/4, y-1/4, z-1/4; (ii) x, y+1/2, z+1/2; (iii) -x+5/4, y+1/4, z+1/4; (iv) x, y-1/2, z-1/2; (v) -x+1, -y+1, z. Figure 2. Packing diagram of complex 1 viewed along the b-axis. The transoid angle values are S2-Co1-O1 = 168.55(6)° and N1-Co1-N4 = 176.71(9)° while the cissoid angle is in the range 81.33 (9)-96.30 (9)°. These values deviate from the ideal values of 180° and 90° confirming the distortion of the octahedron. Furthermore, the angle defined by the S1 and O2 atoms occupying the apical positions, which is 168.55(6) °, deviates severely from the ideal value of 180°. The two ligand molecules are quite planar (RMS 0.1072 Å and 0.0689 Å) and form a dihedral angle of 84.268(3)°. Each ligand molecule forms two five-membered ring upon coordination to the Co(III) cation. The rings Co/C/C/N/O and Co/S/C/N/N formed by each ligand are almost planar and form a dihedral angle of 7.087(1)° and 4.356(1)°, respectively, showing a slight twist in the ligand molecules. The bite angles are 82.08 (10 °) and 87.02(8)° for one ligand and for the second ligand molecule 81.33(9) and 87.24(7)° showing the distortion of the octahedral geometry. The C2-N4 and C8-N5 bond lengths of 1.320 (4) Å and 1.313 (4) Å respectively are compatible with the double bond character [48] while the C-S distances of 1.735 (3) Å and 1.743 (3) Å differ from the distance observed for the double bond character C=S ca. 1.692 Å [49,50] and approaches single bond character C-S (1.837 Å) [45,51]. These facts are indicative that the sulfur atoms coordinated with the Co(III) cation in their thiolate form. Therefore, the Co-S distances of 2.1818(8) and 2.1843(8) Å are shorter than those reported for the complexes [Co(H2L)2]Cl where H2L is 2-[(2-hydroxyphenyl)methylene]hydrazine-N-(2- propenyl)carbothioamide [52] and bis[bis(2-hydroxy-3- methoxybenzaldehydethiosemicarbazonato)cobalt(III)]dithio nate-dimethylformamide-methanol [53] in which the sulfur atom coordinated with the Co(III) in its thione form. In the anionic unit [Co(NSC)4]2-, both anionic N-donor thiocyanates are quasi-linear with angle 179.2(4)° [N7-C10-S3] and 178.1(4)° [N8-C11-S4]. These anionic N-donor thiocyanates bind almost linearly to the cobalt(II) ion with angle Co2-N-CS in the range of 158.2(4)° and 169.8(4)°. The Co2-N distances of 1.955(4) Å and 1.942 (4) Å are in accordance with the values reported for Co-NNCS [54]. The geometry around the tetracoordinated Co2 cation is determined by the distortion index or the tetragonality parameter [55] τ4 = (360° - α - β)/141 where α and β are the two largest angles around the metal center. The expected values for τ4 are zero for a perfect square plane and one for a perfect tetrahedron. The value of τ4, which is 0.9677, suggests a slightly distorted tetrahedral geometry around the Co2 cation. The structure of the complex is consolidated by numerous inter- and intra-molecular hydrogen bonds. The cationic unit, half of the anionic unit, and the free methanol of the asymmetric unit are connected by intramolecular hydrogen bonds of type Namino-H···Omethanol (N6-H6B···O3), Omethanol-H···SNCS (O3-H3···S3) and CMe-H···SNCS (C7-H7A···S4). Intermolecular hydrogen bond of type Oalcoholic-H···Nhydrazinyl (O1-H1···N2i ; i = -x+5/4, y-1/4, z- 1/4); Namino-H···SNCS (N3-H3A···S3ii ; ii = x, y+1/2, z+1/2); Namino- H···Oalcoholic (N3-H3B···O1iii), Oalcoholic-H···NNCS (O2-H2···N5iii ; iii = -x+5/4, y+1/4, z+1/4) and Omethanol-H···Namino (O3-H3···N3iv ; iv = x, y-1/2, z-1/2) and weak intramolecular hydrogen bonds involving CMethyl-H···Sthione (C7-H7A···S2i) and (C3-H3E···S1iii) (i = -x+5/4, y-1/4, z-1/4 and iii = -x+5/4, y+1/4, z+1/4), CMethylene- H···Omethanol (C5-H5B···O3iii); CMethanol-H···Nhydrazinyl (C9- H9A···N2v; v = -x+1, -y+1, z) link cationic unit, half of the anionic unit and free methanol belonging to different asymmetric units. The combined hydrogen bonds links give rise to a three- dimensional network architecture (Figure 2, Table 4). 3.2.2. Complex 2 The hexacoordinated mononuclear compound 2 crystal- lizes in the monoclinic system with the space group P21/n. The selected bond distances and angles relevant to the coordination sphere of the complex are given in Tables 2 and 3, respectively. The ORTEP representation of complex 2 formulated as {[Ni(H2L)2]·[(NCS)2]} is shown in Figure 3. The asymmetric unit contains two neutral molecules ligands, one Ni(II) cation, and two free thiocyanate anions. The metal atom is situated in a N2O2S2 inner. Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 201 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 Table 5. Hydrogen-bond geometry (Å, °) for complex 2. D H A D-H H···A D-A ∠ D-H···A O1 H1 S4i 0.871(9) 2.339(9) 3.1990(16) 169.5(17) O2 H2 N7 0.867(9) 1.942(10) 2.806(3) 174(2) N2 H2A N7ii 0.86 2.15 2.941(2) 153.2 N5 H5 N8 0.86 2.07 2.882(3) 157.8 N3 H3A N7ii 0.86 2.30 3.066(3) 148.9 N3 H3B N8iii 0.86 2.30 3.158(3) 171.7 N6 H6A N8 0.86 2.42 3.162(3) 144.6 N6 H6B S3iv 0.86 2.54 3.390(2) 170.1 C1 H1A S2v 0.97 2.97 3.898(2) 161.3 Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) -x+2, -y+1, -z+1; (iii) -x+3/2, y-1/2, -z+3/2; (iv) x+1/2, -y+3/2, z+1/2; (v) -x+2, -y+2, -z+1. Figure 3. Single crystal structure of complex 2. Figure 4. Packing diagram of complex 2 viewed along the a-axis. Each η3-H2L ligand acts in tridentate fashion through its azomethine nitrogen atom, alcoholic oxygen atom and sulfur atom. The environment around the Ni(II) cation is best described as a strongly distorted octahedral geometry. The equatorial plane is occupied by S1, N4, O1 and N1 with transoid angle values of 169.08 (6) and 160.09 (4)° and cissoid angle values in the range 77.71(6)-104.76(5)°. The angle subtended by the atoms S2 and O2 that occupied the apical positions is 161.09(4)°. All the angle around the Ni(II) cation deviate severely from the ideal values of 90° and 180° expected for a perfect octahedral geometry. Each ligand form two five membered rings which are almost planar [Ni/S/C/N/N (rms: 0.842 Å and 0.0740 Å) and NiNCCO (rms: 0.0956 Å and 0.0440 Å)]. In each ligand molecule, the two five membered rings issued from the coordination form dihedral angles of 10.606(1)° and 8.592(1)°, respectively. The bite angles values in the five membered rings are in the range 77.71(6)°- 83.40(5)°. These observations confirm the severely distorted octahedral geometry around the Ni(II) cation. The two free anionic thiocyanate groups are quasi-linear with an angle N-C- S of 176.1(2)° and 179.6(2)°. The Ni-O bond lengths of 2.1234(14) Å and 2.1240(14) Å are almost equal and are comparable to the similar complex reported by Netalkar et al. [34]. The Ni-S distances (2.3983(5) Å and 2.3867(5) Å) and the C-S distances (1.69 (2) Å and 1.695(2) Å) are indicative that the sulfur atom link to Ni atom in thione form [34]. In fact, the C-S distances are comparable to the corresponding distances and the Ni-S distances and are in the range found for the complex [NiLCl] (where L is 2-acetylpyridine-4-N-p-chlorophenylthio semicarbazone) in which the sulfur atom link to the nickel(II) in its thione form [34]. Intramolecular hydrogen bonds of type Oalcoholic-H···NNCS (O2-H2···N7), Nhydrazinyl-H···NNCS (N5-H5···N8) and Namino- H···NNCS (N6-H6A···N8). Intermolecular hydrogen bond of type Oalcoholic-H···SNCS (O1-H1···S4i ; i = -x+1, -y+2, -z+1); Nhydrazinyl- H···NNCS and Namino-H···NNCS (N2-H2A···N7ii ; ii = -x+2, -y+1, -z+1), Namino-H···NNCS (N3-H3A···N7ii; ii = -x+2, -y+1, -z+1 and N3- H3B···N8iii; iii = -x+3/2, y-1/2, -z+3/2), Oalcoholic-H···NNCS (O2- H2···N5iii ; iii = -x+5/4, y+1/4, z+1/4) and Namino-H···Sthione (N6- H6B···S3iv; iv = x+1/2, -y+3/2, z+1/2) and weak intramolecular hydrogen bonds involving CMethylene-H··· Sthione (C1-H1A···S2v ; v = -x+2, -y+2, -z+1) link the molecules into three-dimensional network architecture (Figure 4, Table 5). 202 Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 Table 6. Hydrogen-bond geometry (Å, °) for complex 3. D H A D-H H···A D-A ∠D-H···A N3 H3A S3i 0.85(2) 2.69(3) 3.482(2) 154(2) N3 H3B S3ii 0.82(3) 2.71(3) 3.507(2) 164(2) N2 H2 S3i 0.79(2) 2.62(2) 3.3799(17) 160(2) O1 H1 S2iii 0.76(3) 2.49(3) 3.2435(17) 173(3) Symmetry codes: (i) x, y, z+1; (ii) x-1, -y+3/2, z+1/2; (iii) x+1, y, z. Figure 5. Single crystal structure of complex 3. Figure 6. Packing diagram of complex 3 viewed along the b-axis. 3.2.3. Complex 3 The penta-coordinated mononuclear compound 3 crystal- lizes in the monoclinic system with the space group P21/c. The selected bond distances and angles relevant to the coordination sphere of the complex are given in Tables 2 and 3, respectively. The ORTEP representation of the complex (3) formulated as [Zn(H2L)(NCS)2] is shown in Figure 5. The complex 3 is build up as a mononuclear. The asymmetric unit contains one Zn(II) ion, one neutral η3-H2L ligand acting in tridentate fashion, and two η1-thiocyane anions coordinated through the nitrogen atom to the metal center. The geometry around the Zn(II) is best discussed with the trigonality parameters. The Addison index [56] τ = (β−α)/60 in which β and α represent the largest angle around the metal center is frequently used to determine the type of environment around the metal center. A perfect trigonal bipyramidal geometry is obtained when the τ value is 1, while a τ value of zero define a perfect square pyramidal geometry. In the penta-coordinated Zn(II) complex the τ value of 0.2403 is indicative of a strongly distorted square pyramidal geometry around the Zn(II) ion. However, the modified index suggested by Konno et al. [57] χ = (β + γ + δ - 2α)/180 (which takes into account the other angles β and α are the largest angles, γ and δ are the other angles around the metal centers without the donor atoms defining β) is used, the χ value of 0.5603 suggests that the geometry around the zinc (II) atom is a strongly distorted trigonal bipyramid. The equatorial plane of the trigonal bipyramid is occupied by three nitrogen atoms N1, N4 and N5. The distortion of the geometry is indicated by the angle values subtended by the N1, N4, and N5 atoms [N4-Zn1-N1 = 135.67(7)°; N5-Zn1-N1 = 107.54(7)° and N4-Zn1-N5 = 114.48(8)°], which deviates severely from the ideal value of 120°. The sum of these angle values of 357.69 deviates from the ideal value of 360°. The apical position are occupied by the sulfur S1 atom of the semicarbazide moiety and the alcoholic oxygen atom with angle value of 150.09(5)° [O1-Zn1-S1] severely deviated from the ideal value of 180°. The whole anionic N-donor thiocyanate groups are quasi-linear with angle values N4-C5-S2 = 179.14(18)° and N5-C6-S3 = 178.31(19)°. These anionic N-donor thiocyanate do not bind linearly to the zinc (II) ion with Zn-N-CS angle values of 168.74(18) and 169.45(18)°. The tridentate ligand forms two five-membered rings Zn1/O1/C1/C2/N1 and Zn1/S1/C4/N2/N1 that share one vertex (N1). The atoms of the rings are quite coplanar with respective rms of 0.821 Å and 0.0432 Å. The mean planes defined by Zn1/O1/C1/C2/N1 and Zn1/S1/C4/N2/N1 form a dihedral angle of 9.351(1)°. The atoms situated in the basal plane N1N4N5Zn1 are quite coplanar. The Zn1 is displaced from the plane defined by the remaining three atoms by about 0.1291(8) Å. The basal plane form with the mean planes of rings dihedral angle of 87.082(1)° (Zn1S1C4N2N1) and 83.746(5)° (Zn1O1C1C2N1). The nitrogen atoms of the η1-thiocyanate groups are strongly linked to the Zn(II) atom as shown by the bond length values of 1.9576(16) Å [Zn1-N4] and 1.9743(18) Å Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 203 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 [Zn1-N5]. These values are comparable to those reported for a similar complex [58,59]. These lower values, compared to the value 2.0973 (15) [Zn1-N1], are due to the anionic character of N4 and N5 of the thiocyanate group, contrary to the neutrality of N1 from the Schiff base. The sulfur atom and the alcoholic oxygen atom that occupy the apical positions are slightly linked to the zinc (II) atom as shown by the distance values of Zn1-S1 = 2.4335(5) Å and Zn-O1 = 2.1846(16) Å. These values are in accordance with those found for similar complexes in which sulfur and oxygen act in nonanionic form [60-62]. No intramolecular hydrogen bond is present in the zinc complex. Intermolecular hydrogen bond of type Namino-H···SNCS and Nhydrazinyl-H···SNCS (N3-H3A···S3i and N2-H2···S3i ; i = x, y, z+1), Namino-H···SNCS (N3-H3B···S3ii ; ii = x-1, -y+3/2, z+1/2), Oalcoholic- H···SNCS (O1-H1···S2iii ; iii = x+1, y, z) link the molecules into three-dimensional network architecture (Figure 6, Table 6). 4. Conclusions Compounds 1, 2 and 3 synthesized using the ligand 1-(1- hydroxypropan-2-ylidene)thiosemicarbazide (H2L) and were characterized with various physicochemical techniques such as elemental analyses, IR and single crystal X-ray diffraction analysis. The complex 1 is formed with one cationic unit containing Co(III) ion and one half anionic unit containing Co(II) ion. Two deprotonated ligand molecules acting in a tridentate fashion coordinate the Co(III) ion, yielding the cationic unit. The anionic unit is formed by a tetrathiocyanate cobalt moiety in which the cobalt(II) center is located on the crystallographic two fold axis of the Fdd2 space group and accounts for only ½ in the asymmetric unit. The Co(III) and the Co(II) metal centers are, respectively, situated in octahedral and tetrahedral environments. In Complex 2, the Ni(II) ion is coordinated by two neutral ligand molecules that act in a tridentate fashion, yielding an octahedral geometry around the nickel(II) center. Two uncoordinated thiocyanate anions are present. In complex 3, the zinc(II) center is coordinated by one neutral ligand molecule and two thiocyanate anions through their nitrogen atoms. The geometry around the Zn(II) center is best described as a distorted trigonal bipyramid environment. Supporting information CCDC-2155588, 2155703 and 2155587 contain the supplementary crystallographic data for complexes 1, 2 and 3, respectively. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, or by e- mailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(0)1223-336033. Disclosure statement Conflict of interest: The authors declare that they have no conflict of interest. Ethical approval: All ethical guidelines have been adhered. Sample availability: Samples of the compounds are available from the author. CRediT authorship contribution statement Conceptualization: Mohamed Gaye, Ousmane Diouf; Methodology: Mohamed Gaye, Ousmane Diouf, Mamadou Sidibé; Software: Cheikh Ndoye, Gregory Excoffier, Ibrahima Elhadji Thiam; Validation: Mohamed Gaye, Ousmane Diouf, Mamadou Sidibé; Formal Analysis: Cheikh Ndoye, Gorgui Awa Seck; Investigation: Cheikh Ndoye, Gorgui Awa Seck; Data Curation: Cheikh Ndoye, Gorgui Awa Seck; Writing - Original Draft: Mohamed Gaye, Ousmane Diouf; Writing - Review and Editing: Mohamed Gaye; Visualization: Cheikh Ndoye, Gregory Excoffier, Ibrahima Elhadji Thiam; Supervision: Mohamed Gaye, Ousmane Diouf. ORCID and Email Cheikh NDoye ndoye314@yahoo.fr https://orcid.org/0000-0002-6799-4973 Grégory Excoffier gregory.excoffier@univ-amu.fr https://orcid.org/0000-0002-6273-1373 Gorgui Awa Seck gorgui-awa.seck@ugb.edu.sn https://orcid.org/0000-0002-6523-9384 Ousmane Diouf ousmanediouf37@yahoo.fr https://orcid.org/0000-0003-3475-9528 Ibrahima Elhadji Thiam i6thiam@yahoo.fr https://orcid.org/0000-0002-4595-8445 Mamadou Sidibé masidibe17@yahoo.fr https://orcid.org/0000-0002-5499-1087 Mohamed Gaye mohamedl.gaye@ucad.edu.sn mlgayeastou@yahoo.fr https://orcid.org/0000-0001-8989-1548 References [1]. Hosseinpoor, H.; Moghadam Farid, S.; Iraji, A.; Askari, S.; Edraki, N.; Hosseini, S.; Jamshidzadeh, A.; Larijani, B.; Attarroshan, M.; Pirhadi, S.; Mahdavi, M.; Khoshneviszadeh, M. Anti-melanogenesis and anti- tyrosinase properties of aryl-substituted acetamides of phenoxy methyl triazole conjugated with thiosemicarbazide: Design, synthesis and biological evaluations. Bioorg. Chem. 2021, 114, 104979. [2]. Tokalı, F. S.; Taslimi, P.; Usanmaz, H.; Karaman, M.; Şendil, K. Synthesis, characterization, biological activity and molecular docking studies of novel schiff bases derived from thiosemicarbazide: Biochemical and computational approach. J. Mol. Struct. 2021, 1231, 129666. [3]. Bakherad, Z.; Mohammadi-Khanaposhtani, M.; Sadeghi-Aliabadi, H.; Rezaei, S.; Fassihi, A.; Bakherad, M.; Rastegar, H.; Biglar, M.; Saghaie, L.; Larijani, B.; Mahdavi, M. New thiosemicarbazide-1,2,3-triazole hybrids as potent α-glucosidase inhibitors: Design, synthesis, and biological evaluation. J. Mol. Struct. 2019, 1192, 192–200. [4]. Aboseada, H. A.; Hassanien, M. M.; El-Sayed, I. H.; Saad, E. A. Schiff base 4-ethyl-1-(pyridin-2-yl) thiosemicarbazide up-regulates the antioxidant status and inhibits the progression of Ehrlich solid tumor in mice. Biochem. Biophys. Res. Commun. 2021, 573, 42–47. [5]. Altalhi, A. A.; Hashem, H. E.; Negm, N. A.; Mohamed, E. A.; Azmy, E. M. Synthesis, characterization, computational study, and screening of novel 1-phenyl-4-(2-phenylacetyl)-thiosemicarbazide derivatives for their antioxidant and antimicrobial activities. J. Mol. Liq. 2021, 333, 115977. [6]. Munaretto, L. S.; Ferreira, M.; Gouvêa, D. P.; Bortoluzzi, A. J.; Assunção, L. S.; Inaba, J.; Creczynski-Pasa, T. B.; Sá, M. M. Synthesis of isothio semicarbazones of potential antitumoral activity through a multicomponent reaction involving allylic bromides, carbonyl compounds and thiosemicarbazide. Tetrahedron 2020, 76, 131231. [7]. Patel, D. B.; Darji, D. G.; Patel, K. R.; Rajani, D. P.; Rajani, S. D.; Patel, H. D. Synthesis of novel quinoline-thiosemicarbazide hybrids and evaluation of their biological activities, molecular docking, molecular dynamics, pharmacophore model studies, and ADME-Tox properties. J. Heterocycl. Chem. 2020, 57, 1183–1200. [8]. Patel, D. B.; Patel, K. D.; Prajapati, N. P.; Patel, K. R.; Rajani, D. P.; Rajani, S. D.; Shah, N. S.; Zala, D. D.; Patel, H. D. Design, synthesis, and biological and in silico study of fluorine-containing quinoline hybrid thiosemicarbazide analogues. J. Heterocycl. Chem. 2019, 56, 2235– 2252. [9]. Šarkanj, B.; Molnar, M.; Čačić, M.; Gille, L. 4-Methyl-7-hydroxy coumarin antifungal and antioxidant activity enhancement by substitution with thiosemicarbazide and thiazolidinone moieties. Food Chem. 2013, 139, 488–495. [10]. Panneerselvam, T.; Mandhadi, J. R. Microwave assisted synthesis and antimicrobial evaluation of novel substituted thiosemicarbazide derivatives of pyrimidine. J. Heterocycl. Chem. 2020, 57, 3082–3088. [11]. Acharya, P. T.; Bhavsar, Z. A.; Jethava, D. J.; Patel, D. B.; Patel, H. D. A review on development of bio-active thiosemicarbazide derivatives: Recent advances. J. Mol. Struct. 2021, 1226, 129268. [12]. Refat, M. S.; El-Deen, I. M.; Anwer, Z. M.; El-Ghol, S. Spectroscopic studies and biological evaluation of some transition metal complexes of Schiff-base ligands derived from 5-arylazo-salicylaldehyde and thiosemicarbazide. J. Coord. Chem. 2009, 62, 1709–1718. [13]. Wang, M.; Wang, L.-F.; Li, Y.-Z.; Li, Q.-X.; Xu, Z.-D.; Qu, D.-M. Transit. Met. Chem. 2001, 26, 307–310. [14]. Yousef, T. A.; Abu El-Reash, G. M.; El-Gamal, O.; Sharaa, B. M. Ligational, DFT, optical band gap and biological studies on Mn(II), Co(II) and http://www.ccdc.cam.ac.uk/data_request/cif mailto:data_request@ccdc.cam.ac.uk mailto:ndoye314@yahoo.fr https://orcid.org/0000-0002-6799-4973 mailto:gregory.excoffier@univ-amu.fr https://orcid.org/0000-0002-6273-1373 mailto:gorgui-awa.seck@ugb.edu.sn https://orcid.org/0000-0002-6523-9384 mailto:ousmanediouf37@yahoo.fr https://orcid.org/0000-0003-3475-9528 mailto:i6thiam@yahoo.fr https://orcid.org/0000-0002-4595-8445 mailto:masidibe17@yahoo.fr https://orcid.org/0000-0002-5499-1087 mailto:mohamedl.gaye@ucad.edu.sn mailto:mlgayeastou@yahoo.fr https://orcid.org/0000-0001-8989-1548 204 Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 Ni(II) complexes of ethyl and allyl thiosemicarbazides ending by thiazole group. J. Mol. Liq. 2018, 251, 423–437. [15]. Cortés, L.; Okio, C. K. Y. A.; Brandão, P. F. B. Tin(IV) complexes of 1,5- diphenylthiocarbazone and thiosemicarbazide: Synthesis, X-ray characterization, and biological activity. Phosphorus Sulfur Silicon Relat. Elem. 2011, 186, 1356–1360. [16]. Huedo, C.; Zani, F.; Mendiola, A.; Pradhan, S.; Sinha, C.; López-Torres, E. Synthesis, antimicrobial activity and molecular docking of di- and triorganotin (IV) complexes with thiosemicarbazide derivatives: Synthesis, antimicrobial activity and docking of organotin complexes. Appl. Organomet. Chem. 2019, 33, e4700. [17]. Yusof, E. N. M.; Ravoof, T. B. S. A.; Page, A. J. Cytotoxicity of Tin(IV)- based compounds: A review. Polyhedron 2021, 198, 115069. [18]. Anita, K.; Rajmuhon Singh, N. Absorption spectral analysis of 4f-4f transitions for the complexation of Pr(III) and Nd(III) with thiosemicarbazide in absence and presence of Zn(II) in aqueous and organic solvents. Spectrochim. Acta A Mol. Biomol. Spectrosc. 2011, 81, 117–121. [19]. Panja, A.; Eichhorn, D. M. Mono- and di-nuclear nickel(II) complexes with mixed N/S-donor ligands: Syntheses, structures and physical properties. Inorganica Chim. Acta 2012, 391, 88–92. [20]. Arion, V.; Wieghardt, K.; Weyhermueller, T.; Bill, E.; Leovac, V.; Rufinska, A. Synthesis, structure, magnetism, and spectroscopic properties of some mono- and dinuclear nickel complexes containing noninnocent pentane-2,4-dione bis(S-alkylisothiosemicarbazonate)- derived ligands. Inorg. Chem. 1997, 36, 661–669. [21]. Raman, N.; Selvan, A.; Manisankar, P. Spectral, magnetic, biocidal screening, DNA binding and photocleavage studies of mononuclear Cu(II) and Zn(II) metal complexes of tricoordinate heterocyclic Schiff base ligands of pyrazolone and semicarbazide/thiosemicarbazide based derivatives. Spectrochim. Acta A Mol. Biomol. Spectrosc. 2010, 76, 161–173. [22]. Chandra, S.; Sangeetika, X. EPR, magnetic and spectral studies of copper(II) and nickel(II) complexes of schiff base macrocyclic ligand derived from thiosemicarbazide and glyoxal. Spectrochim. Acta A Mol. Biomol. Spectrosc. 2004, 60, 147–153. [23]. Shaikh, A.; Mukherjee, P.; Ta, S.; Bhattacharyya, A.; Ghosh, A.; Das, D. Oxidative cyclization of thiosemicarbazide: a chemodosimetric approach for the highly selective fluorescence detection of cerium(iv). New J Chem 2020, 44, 9452–9455. [24]. Wang, Y.; Chang, H.-Q.; Wu, W.-N.; Mao, X.-J.; Zhao, X.-L.; Yang, Y.; Xu, Z.-Q.; Xu, Z.-H.; Jia, L. A highly sensitive and selective colorimetric and off–on fluorescent chemosensor for Cu2+ based on rhodamine 6G hydrazide bearing thiosemicarbazide moiety. J. Photochem. Photobiol. A Chem. 2017, 335, 10–16. [25]. Angupillai, S.; Hwang, J.-Y.; Lee, J.-Y.; Rao, B. A.; Son, Y.-A. Efficient rhodamine-thiosemicarbazide-based colorimetric/fluorescent ‘turn- on’ chemodosimeters for the detection of Hg2+ in aqueous samples. Sens. Actuators B Chem. 2015, 214, 101–110. [26]. Salavati-Niasari, M. Host (nanocage of zeolite–Y)/guest (manganese(II), cobalt(II), nickel(II) and copper(II) complexes of 12- membered macrocyclic Schiff-base ligand derived from thiosemicarbazide and glyoxal) nanocomposite materials: Synthesis, characterization and catalytic oxidation of cyclohexene. J. Mol. Catal. A Chem. 2008, 283, 120–128. [27]. Pouramiri, B.; Tavakolinejad Kermani, E. Lanthanum(III) chloride/ chloroacetic acid as an efficient and reusable catalytic system for the synthesis of new 1-((2-hydroxynaphthalen-1-yl)(phenyl)methyl) semicarbazides/thiosemicarbazides. Arab. J. Chem. 2017, 10, S730– S734. [28]. Maurya, M. R.; Sarkar, B.; Kumar, A.; Ribeiro, N.; Miliute, A.; Pessoa, J. C. New thiosemicarbazide and dithiocarbazate based oxido vanadium(iv) and dioxidovanadium(v) complexes. Reactivity and catalytic potential. New J Chem 2019, 43, 17620–17635. [29]. Refat, M. S.; El-Metwaly, N. M. Spectral, thermal and biological studies of Mn(II) and Cu(II) complexes with two thiosemicarbazide derivatives. Spectrochim. Acta A Mol. Biomol. Spectrosc. 2012, 92, 336– 346. [30]. Zhao, Y.; Wang, Y.; Wu, Q.; Lin, J.; Wu, S.; Hou, W.; Wu, R.; Luo, G. New tricks for an old dog: Visible light-driven hydrogen production from water catalyzed by fac- and mer- geometrical isomers of tris(thiosemicarbazide) cobalt(III). Cuihua Xuebao/Chin. J. Catalysis 2018, 39, 517–526. [31]. El-Gammal, O. A.; Fouda, A. E.-A. S.; Nabih, D. M. Novel Mn2+, Fe3+, Co2+, Ni2+ and Cu2+complexes of potential OS donor thiosemi carbazide: Design, structural elucidation, anticorrosion potential study and antibacterial activity. J. Mol. Struct. 2020, 1204, 127495. [32]. Singh, A.; Bharty, M. K.; Dani, R. K.; Singh, S.; Kushawaha, S. K.; Singh, N. K. Manganese(II) and zinc(II) complexes of 4-phenyl(2-methoxy benzoyl)-3-thiosemicarbazide: Synthesis, spectral, structural characterization, thermal behavior and DFT study. Polyhedron 2014, 73, 98–109. [33]. Başaran, E.; Sıcak, Y.; Sogukomerogullari, H. G.; Karaküçük-Iyidoğan, A.; Oruç-Emre, E. E.; Sönmez, M.; Öztürk, M. Synthesis of novel chiral metal complexes derived from chiral thiosemicarbazide ligands as potential antioxidant agents. Chirality 2019, 31, 434–444. [34]. Netalkar, P. P.; Netalkar, S. P.; Revankar, V. K. Transition metal complexes of thiosemicarbazone: Synthesis, structures and invitro antimicrobial studies. Polyhedron 2015, 100, 215–222. [35]. Dolomanov, O. V.; Bourhis, L. J.; Gildea, R. J.; Howard, J. A. K.; Puschmann, H. OLEX2: a complete structure solution, refinement and analysis program. J. Appl. Crystallogr. 2009, 42, 339–341. [36]. Sheldrick, G. M. SHELXT - integrated space-group and crystal- structure determination. Acta Crystallogr. A Found. Adv. 2015, 71, 3– 8. [37]. Sheldrick, G. M. Crystal structure refinement with SHELXL. Acta Crystallogr. C Struct. Chem. 2015, 71, 3–8. [38]. Keypour, H.; Mahmoudabadi, M.; Shooshtari, A.; Bayat, M.; Soltani, E.; Karamian, R.; Farida, S. H. M. Synthesis, spectral, theoretical and antioxidant studies of copper (II) and cobalt (III) macroacyclic Schiff- base complexes containing homopiperazine moietiy. Chem. Data Coll. 2020, 26, 100354. [39]. Joshi, R.; Kumari, A.; Singh, K.; Mishra, H.; Pokharia, S. Synthesis, structural characterization, electronic structure calculation, molecular docking study and biological activity of triorganotin(IV) complexes of schiff base (E)-4-amino-3-(2-(2-hydroxybenzylidene) hydrazinyl)-1H-1,2,4-triazole-5(4H)-thione). J. Mol. Struct. 2019, 1197, 519–534. [40]. Laachir, A.; Rhoufal, F.; Guesmi, S.; Ketatni, E. M.; Jouffret, L.; Hlil, E. K.; Sergent, N.; Obbade, S.; Bentiss, F. Cobalt(II) coordination complex with 2,5-bis(pyridine-2-yl)-1,3,4-thiadiazole and thiocyanate as co- ligand: Synthesis, crystal structure, Hirshfeld surface analysis, spectroscopic, thermal and magnetic properties. J. Mol. Struct. 2020, 1208, 127892. [41]. Sarkar, B. N.; Bhar, K.; Kundu, S.; Fun, H.-K.; Ghosh, B. K. Synthesis, molecular and crystalline architectures, and properties of mononuclear cobalt(II) thiocyanates containing a symmetrical tailored diimine/an unsymmetrical bidentate Schiff base. J. Mol. Struct. 2009, 936, 104–111. [42]. Hannachi, A.; Valkonen, A.; Gómez García, C. J.; Rzaigui, M.; Smirani, W. Synthesis of isomorphous cobalt and nickel thiocyanate coordination compounds: Effect of metals on compound properties. Polyhedron 2019, 173, 114122. [43]. Chandra, S.; Gupta, L. K.; Sangeetika Spectroscopic, cyclic voltammetric and biological studies of transition metal complexes with mixed nitrogen-sulphur (NS) donor macrocyclic ligand derived from thiosemicarbazide. Spectrochim. Acta A Mol. Biomol. Spectrosc. 2005, 62, 453–460. [44]. Banerjee, A.; Chattopadhyay, S. A benzoate bridged dinuclear mixed valence cobalt(III/II) complex with CoIIIO4CoII core: Synthesis, structure and investigation of its phenoxazinone synthase mimicking activity. Polyhedron 2020, 177, 114290. [45]. Mansour, A. M. Crystal structure, DFT, spectroscopic and biological activity evaluation of analgin complexes with Co(ii), Ni(ii) and Cu(ii). Dalton Trans. 2014, 43, 15950–15957. [46]. Sadhu, M. H.; Solanki, A.; Kumar, S. B. Mixed ligand complexes of copper(II), cobalt(II), nickel(II) and zinc(II) with thiocyanate and pyrazole based tetradentate ligand: Syntheses, characterizations and structures. Polyhedron 2015, 100, 206–214. [47]. Chandra, S.; Hooda, S.; Tomar, P. K.; Malik, A.; Kumar, A.; Malik, S.; Gautam, S. Synthesis and characterization of bis nitrato[4- hydroxyacetophenonesemicarbazone) nickel(II) complex as ionophore for thiocyanate-selective electrode. Mater. Sci. Eng. C Mater. Biol. Appl. 2016, 62, 18–27. [48]. Gorczyński, A.; Zaranek, M.; Witomska, S.; Bocian, A.; Stefankiewicz, A. R.; Kubicki, M.; Patroniak, V.; Pawluć, P. The cobalt(II) complex of a new tridentate Schiff-base ligand as a catalyst for hydrosilylation of olefins. Catal. Commun. 2016, 78, 71–74. [49]. Zhao, R.-G.; Zhang, W.; Li, J.-K.; Zhang, L.-Y. (E)-2-Hydr-oxy-3- methoxy-benzaldehyde thio-semicarbazone. Acta Crystallogr. Sect. E Struct. Rep. Online 2008, 64, o1113. [50]. Vrdoljak, V.; Dilović, I.; Rubcić, M.; Kraljević Pavelić, S.; Kralj, M.; Matković-Calogović, D.; Piantanida, I.; Novak, P.; Rozman, A.; Cindrić, M. Synthesis and characterisation of thiosemicarbazonato molybdenum(VI) complexes and their in vitro antitumor activity. Eur. J. Med. Chem. 2010, 45, 38–48. [51]. Gizatullin, A.; Becker, J.; Islamov, D.; Serov, N.; Schindler, S.; Klimovitskii, A.; Shtyrlin, V. Synthesis and structure of a complex of copper(I) with l-cysteine and chloride ions containing Cu12S6 nanoclusters. Acta Crystallogr. E Crystallogr. Commun. 2021, 77, 324– 330. [52]. Orysyk, S. I.; Repich, G. G.; Bon, V. V.; Dyakonenko, V. V.; Orysyk, V. V.; Zborovskii, Y. L.; Shishkin, O. V.; Pekhnyo, V. I.; Vovk, M. V. Novel Fe(III), Co(III), Ni(II), Cu(II) coordination compounds involving 2-[(2- hydroxyphenyl)methylene]hydrazine-N-(2-propenyl)- carbothioamide as ligand: Synthesis, crystal structures and spectral characteristics. Inorganica Chim. Acta 2014, 423, 496–503. [53]. Rusanova, J. A.; Kokozay, V. N.; Petrusenko, S.; Plyuta, N. Synthesis and crystal structure of a solvated CoIII complex with 2-hy-droxy-3-meth- Ndoye et al. / European Journal of Chemistry 13 (2) (2022) 196-205 205 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.2.196-205.2253 oxy-benzaldehyde thio-semicarbazone ligands. Acta Crystallogr. E Crystallogr. Commun. 2021, 77, 1130–1134. [54]. Kalinke, L. H. G.; Cardoso, J. C. O.; Rabelo, R.; Valdo, A. K.; Martins, F. T.; Cano, J.; Julve, M.; Lloret, F.; Cangussu, D. From paramagnetic to single- molecule magnet behaviour in heterobimetallic compounds containing the tetrakis(thiocyanato‐ κN )cobaltate(II) anion: From paramagnetic to single-molecule magnet behaviour in hetero bimetallic compounds containing the tetrakis(thiocyanato-κN) cobaltate(II) anion. Eur. J. Inorg. Chem. 2018, 2018, 816–825. [55]. Singh, Y. P.; Patel, R. N.; Singh, Y.; Choquesillo-Lazarte, D.; Butcher, R. J. Classical hydrogen bonding and stacking of chelate rings in new copper(ii) complexes. Dalton Trans. 2017, 46, 2803–2820. [56]. Addison, A. W.; Rao, T. N.; Reedijk, J.; van Rijn, J.; Verschoor, G. C. Synthesis, structure, and spectroscopic properties of copper(II) compounds containing nitrogen–sulphur donor ligands; the crystal and molecular structure of aqua[1,7-bis(N-methylbenzimidazol-2′- yl)-2,6-dithiaheptane]copper(II) perchlorate. J. Chem. Soc., Dalton Trans. 1984, 1349–1356. [57]. Konno, T.; Tokuda, K.; Sakurai, J.; Okamoto, K.-I. Five-Coordinate Geometry of Cadmium(II) with Octahedral Bidentate-S,SComplex- Ligandcis(S)-[Co(aet)2(en)]+(aet=2-aminoethanethiolate): Synthesis, Crystal Structures and Interconversion of S-Bridged CoIIICdII Polynuclear Complexes. Bull. Chem. Soc. Jpn. 2000, 73, 2767–2773. [58]. Das, S.; Bhar, K.; Chattopadhyay, S.; Mitra, P.; Smith, V. J.; Barbour, L. J.; Ghosh, B. K. Syntheses, structures and luminescence behaviours of Group 12 metal(II) thiocyanate complexes with a tetradentate Schiff base: Variation in molecular and crystalline architectures with the change of congeneric metal ions. Polyhedron 2012, 38, 26–35. [59]. Roy, S.; Sarkar, B. N.; Bhar, K.; Satapathi, S.; Mitra, P.; Ghosh, B. K. Syntheses, structures and luminescence behaviors of zinc(II) complexes containing a tetradentate Schiff base: Variation in nuclearity and geometry with the change of halide/pseudohalide/ carboxylate and counter anion. J. Mol. Struct. 2013, 1037, 160–169. [60]. Shaikh, I.; Vohra, A.; Devkar, R.; Jadeja, R. Synthesis, characterization, structural features and cytotoxicity of innovative zinc(II) complex derived from ONS-donor thio-Schiff base of acyl pyrazolone. Eur. J. Chem. 2019, 10, 131–138. [61]. Ibrahim, M. M.; Shaban, S. Y. Synthesis, characterization, and crystal structures of hydrotris(2-mercapto-1-imidazolyl)borate-based zinc (II) and copper(I) complexes. Inorganica Chim. Acta 2009, 362, 1471– 1477. [62]. Li, Y.-P.; Zang, H.; Sun, D.; Ming, J.; Su, G.-F. Crystal structure of bis2- [bis(2-hydroxyethyl)amino]ethanol-κ3O,N,O′zinc terephthalate. Acta Crystallogr. Sect. E Struct. Rep. Online 2014, 70, m361–m362. Copyright © 2022 by Authors. This work is published and licensed by Atlanta Publishing House LLC, Atlanta, GA, USA. The full terms of this license are available at http://www.eurjchem.com/index.php/eurjchem/pages/view/terms and incorporate the Creative Commons Attribution-Non Commercial (CC BY NC) (International, v4.0) License (http://creativecommons.org/licenses/by-nc/4.0). By accessing the work, you hereby accept the Terms. This is an open access article distributed under the terms and conditions of the CC BY NC License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited without any further permission from Atlanta Publishing House LLC (European Journal of Chemistry). No use, distribution or reproduction is permitted which does not comply with these terms. Permissions for commercial use of this work beyond the scope of the License (http://www.eurjchem.com/index.php/eurjchem/pages/view/terms) are administered by Atlanta Publishing House LLC (European Journal of Chemistry). http://www.eurjchem.com/index.php/eurjchem/pages/view/terms http://creativecommons.org/licenses/by-nc/4.0 http://www.eurjchem.com/index.php/eurjchem/pages/view/terms 1. Introduction 2. Experimental 2.1. Materials and instrumentation 2.2. Synthesis of ligand 1-(1-hydroxypropan-2-ylidene) thiosemicarbazide (H2L) 2.3. Synthesis of complexes 1, 2, and 3 2.4. X-ray data collection, structure determination, and refinement 3. Results and discussion 3.1. General study 3.2. Description of the structures 3.2.1. Complex 1 3.2.2. Complex 2 3.2.3. Complex 3 4. Conclusions Supporting information Disclosure statement CRediT authorship contribution statement ORCID and Email References PrintField10: PrintField11: PrintField12: PrintField13: PrintField14: PrintField15: PrintField16: PrintField17: PrintField18: PrintField19: PrintField20: PrintField21: PrintField22: PrintField23: PrintField24: PrintField25: PrintField26: PrintField27: PrintField28: PrintField29: