Microsoft Word - 115-129 Chemistry | 115 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 Synthesis and Characterization of Schiff Base Derived From Chitosan and Its Complexes With (Co+2, Ni+2 and Cu+2) Mahmoud A. Al-Issa Ayat A. Abbas Dept. of Chemistry / College of Science for Women / University of Baghdad Fadhel S. Matty Dept. of Chemistry / College of Education for Pure Science (Ibn Al-Haitham) / University of Baghdad Received in: 25/ May/2015, Accepted in :10/June/2015   Abstract In this research, new Schiff base is derived from chitosan O-nitrobenzyldehyde and its complexes were synthesized. All compounds were characterized by FT-IR, UV-Visible, TGA, DTA, TG and molar conductivity with melting point. The results showed that Schiff base was coordinated via nitrogen atom azomethine with the center metal ions Co+2,Ni+2 and Cu+2 behaving monodentate ligand and forming complexes with molecular formula [M(L)Cl2H2O] The tetrahedral geometrical was suggested for all prepared complexes based on the characterization data for all techniques. +2,Cu+2, Ni+2M = Co Key words: chitin, chitosan, schiff base, complexes.                                                Chemistry | 116 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016     Introduction Chitosan is typically obtained by deacetylation of chitin under alkaline conditions [1]. Chitosan displays interesting properties such as biocompatibility, biodegradability [2,3] and its degradation products are non-toxic, non-immunogenic and non- carcinogenic[4,5].Therefore, chitosan has prospective applications in many fields such as biomedicine, waste water treatment. Recently, there has been a growing interest in the chemical modification of chitosan in order to improve its properties and widen its application [6,7].Schiff base containing imine groups can be prepared from reaction between active carbonyl groups and amino groups[8]. Schiff bases and their metal complexes have received a great deal of attention during the last decade in order to prepare new sets of these bases and their transition metal complexes [9].These complexes have proved that it is antitumer and has carcinostatic activities [10]. In this study we report the grafting modification of chitosan with O-nitrobenzyldehyde, The complexes were synthesized from modified chitosan and (Co+2,Ni+2 and Cu+2) metals ions. Experimental Polymer and reagents Chitosan with 85% degree of deacetylation was obtained from J&K Iran and all reagents and solvents were obtained from BDH and used without further purification. Synthesis of chitosan Schiff base (CSB) [11] 0.5 gm Chitosan was dissolved in a mixed 10 ml of methanol with 5 drops of acetic acid and stirred at room temperature for 30 min. Then, 0.015gm o- nitrobenzaldehyde was added to the mixture. The mixture was stirred and heated at 60°C for 12 h under water bath heating. Chemistry | 117 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 After cooling, the crude product was washed with Methanol to the point of colorless filtrate. The product was dried at 60°C in vacuum for 24 h. The synthetic route of target compounds is shown in scheme. Scheme synthesis of chitosan schiff base (L) Preparation of chitosan schiff base of (Co+2, Ni+2 and Cu+2) complexes 0.2 gm of Schiff base ligand mixed with 0.2 gm of (CoCl2.6H2O NiCl2.6H2O,CuCl2.2H2O,) were dissolved in DMSO, and stirred and heated at 60°C for 12 h under water bath heating. After cooling, the crude complex was washed with DMSO, subsequently washed to colourlessness by excess amounts of water, and then dried at 60°C in vacuum for 24 h. The synthetic route of target compounds is shown in scheme . Scheme (1) Chemistry | 118 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 Instruments FTIR spectrophotometer of shimadzu company as KBr disc in the wavelength range f (4000-400) cm-1 were recorded using IR prestige – 21, single beam path laser. Electrical conductivity measurement of the complexes was recorded at (25C0) with 0.001M, all complexes were dissolved in DMSO. The electronic spectra were measured in the range of 200- 1100 nm for 10-3 by usig DMSO solvent by using UV-Visible spectrophotometer type shimadzu UV-160A using quartz cell of (1.0 cm) length. TG-DSC were carried out by STA PT-1000 (Linseis) instrument. Results and discussion Firstly chitosan and the target productions were characterized by FTIR, UV-Visible spectroscopy and Thermal analysis. The yellow ligand were formed and soluble in DMSO solvent. Table (1) shows physical behavior of the ligand and its complexes with metal ions (Co+2, Ni+2 and Cu+2). FTIR – characterization of chitosan Schiff –base ligands and their metal complexes The FTIR spectra for prepared ligand and its (Co+2, Ni+2 and Cu+2) complexes are shown in Figure [(1) and (2)]. The assignment of the characteristic band are summarized in Table (2). The (FT-IR) spectrum for the ligand (L), Figure (1) shows bands at (3037) cm-1, (1022) cm-1, (2885) cm-1 and (3105) cm-1 due to stretching frequency ѵ(O—H), ѵ(C—O—H), ѵ(C—H) aldehydic and ѵ(C—H) aromatic. The new band at (1643) cm-1 was due to ѵ(C=N) group of the azomethine stretching frequency of the ligand (L3), this refers to formation of Schiff base compound [12,13]. The IR spectra of all prepared complexes exhibited broad band at range (3379 – 3444) cm-1, that may be attributed to (O-H)due to starting material (polymer), and the band ant range (3670- 3750) cm-1, that may be attributed to ѵ (O-H) water molecules in molecular formula of all complexes [14,15] the stretching frequency of azomethine group ѵ (C= N) of the free ligand was shifted to lower or high frequency at range (+8 to -4) cm-1 with ligand complexes , this shift to lower or high frequency may be due to involved nitrogen atom of azomethine group in coordination with metal ions and delocalization of metal electronic density to the ligands (π –system)[16,17],(HOMO→ LUMO) ,where: HOMO = Highest Occupied Molecular Orbital LUMO = Lowest unoccupied Molecular Orbital Assignment of proposed coordination sites is further supported by the appearance of medium bands at range (432-459) cm-1 which could be attributed to ѵ(M—N)[18]. The IR spectra of ligand and all prepared complexes, suggested that the ligand behaves as monodentate ligand via N atom of azomethine group. Electronic spectra of the ligand and its metal complexes The UV-Vis. Spectrum of ligand, Figure (3), displayed one absorption peak, the peak at [(262nm,38167cm-1)] were attributed to (π →π*)electronic transition [19]. The electronic spectra of Co+2 complex figure (4) showed three additional absorption peaks. The first peak at range (496nm-20408cm-1) the second peak at [(569 nm,17574cm-1),(859 Chemistry | 119 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 nm,11641cm-1) and (569nm,17574cm-1)], were attributed to (d-d) spin –allowed electronic transition type 4T2F→4T1p, 4A2F→4T1F and 4A2F→4T1F, respectively, characteristic tetrahedral geometry around Co+2[20,21]. The UV-Vis spectra of Ni+2 complexes with all, Figures (5) display two additional absorption peaks. The first peak at [(601nm,16638cm-1)] and the second peak at [(846nm,11820cm-1)] respectively, were due to (d-d) spin-allowed electronic transition type 3T1F→1T2 and 3T1F→3T1P respectively, which was a good agreement for tetrahedral geometry of Ni+2 complex [22,23].The UV-Vis spectra of Cu+2 complexes with ligand display one additional absorption peak (750nm, 13333 cm-1) for ligand complexes,were attributed to (d-d) spin-allowed electronic transition type (2T2→2E), confirming tetrahedral geometry about Cu+2[24]. The electronic spectra for ligand complexs are summarized in Table (3) together with electronic transition and suggested geamotrics. 3-3Molar Conductance The molar conductance values, Table (3) of the soluble complexes in DMSO solvent in (10- 3M) solution at room temperature refers to non-electrolytic nature [25]. Thermal analysis The TG-DTA curves of chitosan ,modified chitosan, Their complexes were obtained at the heating rate of 10C0 min-1 under nitrogen, figures from [(6) to (8)]and the detailed data are shown in Table (4). The TG and DTG curves Figure (6) of chitosan show relatively rapid decomposition in the first (29.3-99.3 0C) and second (215.8-3395 0C) steps with TDTG peaks at 67 0C and 270 0C. The very large and strongly sharp TDTG peak observed for the first step at 67 0C is preceded by a sharp endothermic peak (Tdta) in DTA curve at 70.7 0C 1.97% and 46.46% mass losses in the first and second steps correspond to the release of (2H2O)and (CO2+C2H3NN) fragments[cal.2.10% and 45.8%] respectively. The TG and DTG curves of modified chitosan (ligand) curves figure (7) show the DTG peak (TDTG) of the first (28.1-130 0C) and second (245-349.8 0C)steps at 60.8 0C and 249 0C. The strongly sharp exothermic peak (Tdta) observed for the first-step at 60.8 0C was due to a rapid release of (H2O) fragment (found 1.14%,cal. 1.18%). 91.6% mass loss of the second (245-349.8 0C)step with TDTG peak at 249 0C and Tdta at 248.5 0C is to the (CqH8N2O+CO2)fragment (cal. 90.96%). The TG thermogram of Co-Ligand complex was characterized by two decomposition steps in the range [(35-197) and (197-349) C0 ]. The first steps at TDTG of (1300C) ill-defined are consistent with the evolution of (Cl2) only with one coordinated water molecule [(Cal.24.15, found 23.38٪) ].The final ill-defined residue are [(C8H7N2O2)] fragments [(Cal.63.03٪, found 63.23٪ respectively]. The TG thermogram of Ni- ligand complex Figure (8) is characterized by two decomposition steps in the range [(60-160) and (160-320)0C]. The first steps at TDTG of (1150C), ill-defined are consistent with the evolution of (CO2+ClC2HO) only with two coordinated water molecule (Cal 38.01٪, found 37.95٪) and their overlapping peaks. The final ill-defined residue is(C10H8N2ONiCl) fragments [(Cal.61.77, found 61.61٪) respectively]. Chemistry | 120 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 The TG thermogram of Cu-Ligand was characterized by one decomposition steps in the range [47-1460C] . The first steps at TDTG of (74.50C) respectively, ill-defined are consistent with the evolution of [(CO2+C6H6N2Cl2)] only with one coordinated water molecule (Cal 75.15٪, found 74.5٪)]. The broad endothermic peaks at 1340C of Cu-L, , which do not due to correspond to any weight losses in the TG curve, may be due to some rearrangement in the structure of the complexes [26]. According to the above - mentioned analysis, the suggested structures for the prepared complexes are illustrated below O-Nitrobenzyldehyde chitosan complex O]2H2Suggested structure of prepared complexes [M(L)Cl +2,Cu+2, Ni+2M = Co References 1-. Tomihata ,K. and Ikada, Y.(1997).Biomaterials (18) 567–575. 2- Kumar, R.; Muzzarelli, M.N.V.; .Muzzarelli, R.A.A.; Sashiwa, C.H.and Domb, A. (2004) J. Chem. Rev.: 104 6017–6084. 3- . Sanford, P.A in: Skjak-Braek, G.; Anthonsen, T.and Sanford ,P.A. (Eds.) 1989, Chitin and Chitosan-sources, Chemistry, Biochemistry, Physical Properties and Applications, Elsevier, London,. 51–70. 4- Muzzarelli, R.A.A. (1997) Cell Mol. Life Sci. (53) 131–140. 5- Bersch, P.C.; Nies, B. and A. Liebendorfer, (1995) J.Mater. Sci. Mater.Med.( 6 )231–240. 6- Kurita, K.; Kojima,T. ; Munakata,T; Akao, H.; Mori, T.and Nishiyama, Y. (1998) et al., Chem. Lett. 27 317–318. 7- . Heras, A.; Rodriguez, N.M.; Ramos,V.M. (2001) Carbohydr. Polym. (44 )1–8. 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Morill, T.C"Spectrometric identification of Organic compound" 4th ed, john wiley and Sons, lnc.New York,(1978). 14- AL-Hamdani ,Abbas,A.S,Balkhi ,A.M.,Falah,A.and shaker ,SH.A., J.chil chem .soc.,59(4) (2014) : 2248 – 2259. 15- Nakamoto, K., (1978)"Infrared and Raman Spectraof Inorgaic and Coordination Compounds" 3rd ed., John Wiley & Sons, New York. 16- Ali, Mirza, M.A. .; Nazimuddin, A.H. ;Dhar, M. p.k.and Putcher, R.J., (2002)Transition 14 et.chem .27: 27 – 33. 17- Anupama, B.; Padmaja, M. and. Kumari, C.G .E-J .of chem. (2012), 9(1): 389 -400. 18- Moamen, S.R.; EL-Deen, M.I. Ibrahim, K.H. and EL-Ghool, S. (2006) Spectrochimica Acta part, A., 65:1208-1220. 19- Manjula, B. and Antony, S.A. (2013)꞉ AsianJ.of biochem.and pharm.Res., Issue1.,3168- 178. 20- Anitha, C.; Sumathi, S.; Tharmaraj, P. and Sheela,C.D. (2011) International d.Inorganic chemistry., Article ID493942,8. 21- Lever, A.B.P.,(1984) "Inorganic Electronic Spectroscopy",2nded Elsevier, New York. 22- Kalyoncuoglu, N, Rollas, S. Sur-Altiner, D. Yegenoglu,Y. and Ang, Pharmazie.,O. (1992) 47,769. Chemistry | 122 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 23- Al-Mukhtar, S.E. and. Mustafa, I.A (1988) "Inorganic and coordination chemistry"., Iraq.Musal611-646. 24- El-Asmy, A.A.; Al-Ansi, T.Y. and shaiba, Y.M (1989)Trans.Meta.chem., 14 446. 25- El-Rhaman , G.A.A. (2003) ((MSc. Thesis))., Al-Azhar University, Egypt. 26- Manjula, B. and Antony, S.A. (2013)Asian J.of biochem.and pharm.Res., Issue1.,3꞉168- 178. Table (1): Shows physical behavior of the ligand with metal ions (Co+2, Ni+2 and Cu+2). Table (2) :Infrared spectral data (cm-1) for the ligands and complexes Symbol Colors Melting point Chitosan Off white 284 NBC(L) Yellow 250 CoL Light Red 266 NiL Light Green 232 CuL Olive Green 210 F ig s. M -N C -H a ro m . C -H a ld . C = N C -H -O H 2 O O H R O H C o m p . 3 -5 ---- 3105 2885 1643 1022 ----- 3437 NBC(L) 3 -6 432 3090 2916 2881 1643 1026 3720 3750 3417 CoL 3 -7 451 3008 2916 1647 1022 3680 3740 3444 NiL 3 -8 459 3005 2916 1651 1026 3750 3394 CuL Chemistry | 123 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 Table (3) Electronic spectral data of ligand and it ̓s complexes and molar conductance for all complexes Table (4) Characterization parameter of thermal decomposition (100min-1) for compound Compound ʎ(nm) Ѵ-cm-1 ABS Assignment ∆ohm-1 cm2.mol-1 Suggested structure Fig. NBC(L) 262 38167 1.727 π →π* ------ ----- 3-5 CoL 260 342 490 569 859 38461 29239 20408 17574 11641 1.220 1.310 0.062 0.146 0.140 π →π* C.T 4T2F→4T2p 4A2F→4T1F 4A2F→4T1F 9.70 Tetrahedral 3-6 NiL 274 325 601 846 36496 30769 16638 11820 1.509 1.701 0.231 0.211 π →π* C.T 3T1F→1T2 3T1F→3T1P 4.09 Tetrahedral 3-7 CuL 272 750 36764 13333 1.680 0.196 π →π* 2T2→2E 9.66 Tetrahedral 3-8 F ig u re s Total mass loss٪ Reaction DTA TGA Step Comp. H∆ dtaT Weight mass loss٪ DTGmaxT C0/fT C0Ti/ 3-9 47.73(47.9) O)22(H- end 70.7 1.27(2.10) 67 99.3 29.3 Stage1 Chitosan -(CO2)+C2H3N exo 283.8 46.46(45.8) 270 339.5 215.8 Stage2 3-10 92.74(92.14) -H2O end 60 1.14(1.18) 60.8 130 28.1 Stage1 NBC(L) -C9H8N2+CO2 exo 248.5 91.6(90.96) 249 349.8 245 Stage2 3-11 86.61(87.18) -H2O+Cl2 end 55 23.38(24.15) 130 197 35 Stage1 [Co L] -C8H7N2O2 exo 261 63.23(63.03) 259.6 349 197 Stage2 3-12 99.56(99.8) -2H2O+CO2+ C2HOCl end 120 37.95(38.01) 115 160 60 Stage1 [Ni L] C10H8N2ONiCl exo 232 61.61(61.77) 221.8 320 160 Stage2 3-13 74.5(75.15) H2O+CO2+Cl2+ C6H6N2 end 89 74.5(75.15) 130 146 47 Stage1  [Cu L] Rearrangement to complex end 134      Rearrangement to complex exo 205.1      Chemistry | 124 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 Figure (1): FTIR spectrum of NBC (L) Chemistry | 125 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 Figure (2): FTIR spectrum of CoL complex Figure (3): Electronic spectrum of NBC (L) Chemistry | 126 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 Figure (4): Electronic spectrum of CoL Chemistry | 127 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 Figure (6): Thermal analysis of chitosan Chemistry | 128 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 Figure (7): Thermal analysis of NBC(L) Figure(8): Thermal analysis of Ni Chemistry | 129 2016) عام 2العدد ( 29مجلة إبن الهيثم للعلوم الصرفة و التطبيقية المجلد Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (2) 2016 تحضير وتشخيص قاعده شيف مشتقه من كيتوسان ومعقداته مع االيونات +2and Cu +2, Ni+2Co محمود عبد الجبار العيسى عبد المنعم عباس آيات قسم الكيمياء / كليه العلوم للبنات / جامعه بغداد فاضل سليم متي بغداد/ جامعه )ابن الهيثم ( للعلوم الصرفة التربيةقسم الكيمياء / كليه 2015/حزيران/10:قبل في ، 2015/أيار/25:استلم في الخالصة تحضير قواعد شيف بتفاعل التكثيف من الكيتوسان و اورثو نايترو بنزيلديهايد وكذلك تحضير الرسالةتضمنت . ةالحرارمعقدات هذه الليكندات تحت تاثير لظروف التفاعل مثل درجه ) وطيف FTIRتحت الحمراء ( ةطيف االشع ةبوساط ةشخصت مركبات الكيتوسان قواعد شيف ومعقداتها المحضر واظهرت النتائج بأن الليكند أحادي المخلب من ةالموالري ة) والتوصيليUV-Visible( ةوالمرئي ةفوق البنفسجي عةاالش ووفقا لطرائق التشخيص المشار اليها Cu +2,Ni+2Co,2+ونات الفلزات خالل تناسق ذره النتروجين االزوميثين مع اي . رباعي السطوح Cu +2,Ni+2Co,2+اعاله فأن الشكل الهندسي المقترح لمعقدات الكيتوسان قواعد شيف مع ايونات لكيتوسان والكيتونات المحور لقواعد شيف والمعقدات وجد هناك اختالف في ةالحراري ةاالستقراري ةوتم دراس .لهذه المركبات بسبب اختالف التركيبة الحراري ةاالستقراري .معقدات- قواعد شيف -كيتوسان -: كايتينالمفتاحيةالكلمات