IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 Synthesis and Characterization of New Symmetrical Pyromellitdiimide Derivatives and Their Amic Acids E. T. Ali , K. M. Lazim AL-Aliawy and J. H. Tomma Departme nt of Chemistry, College of Education , Ibn Al-Haitham Unive rsity of Baghdad Re ceived in : 29 March 2011 Accepted in : 30 May 2011 Abstract The new sy mmetry py romellitdiimide [ VII]a- c,n were sy nthesized by two-step reactions from the corresp onding py romellitic dianhy dride . A new sy mmetrical amic acid [VI]a- c,n was sy nthesized by the reaction of py romellitic dianhy dride with different heterocyclic amines in dry acetone . The second r eaction st ep includes intramolecular cyclization of amic acid in the p resence of sodium acetate -acetic anhydride sy stem at 85 0 C. Structures of the sy nthesized comp ounds have been ascertained by their melting p oints , C.H.N analysis , UV-Vis, FT IR and 1 HNMR sp ectroscopy . Key words : Py romellitdiimide , Py romellitic dianhy dride , Py romellitamic diacid Introduction Py romellitdiimides are b est known as segments of highly insulating p olyimides dielectrics, it is though nevertheless quit surp rising that two attempt has been made to fabricate transistor from py romellitdiimide deriv atives . Py romellitdiimides derivatives can be easily p repared by one –step reaction between py romellitic dianhydride and v arious amines . The facile sy nthesis of p y romellitdiimide der ivatives offers an advantage in larges scale sy nthesis due to its high conversion y ield and ease of p urification . M any workers sy nthesized new py romellitimid e deriv atives by using this method in different conditions[1- 7]. Anot her method t o sy nthesis py romellitdiimide der ivatives in cludes two step , firstly sy nthesis of amic acid by nucleophilic addition of amine to acid anhydride, secondly condensation amic acid by heating to y ield pyromellitdiimide by ring closure [8-11]. The pyromellitimides containin g h eterocyclic un its very rare [10,12] , therefor e we decided to sy nthesis and characterized the new amic acid containing thiazole, benzot hiazole or oxadiazole unit and their p y romellitdiimide derivatives. IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 Experime ntal Materials: All the chemicals were supp lied from M erck , Fluka ,GCC and Aldrich ch emicals Co. and used as received. Technique s : FT IR sp ectra were recorded usin g p otassium bromide discs on a shimadzu (8400S) and shi madzu (IR Prest ige-21). 1 HNM R sp ectra were carr ied out by comp any : Bruker , model: u ltra shield 300 M Hz , origin : Switzerland and are reported in p p m(S), DM SO was used as solvent with TM S as an internal st andard. M easurements were mad e at chemist ry department, AL-Alby at university, Elemental microanaly sis (C.H.N) were carried out by a (C.H.N) comp any : Euro vector , model EA3000A origin : Italy . AL-Albay t University , Jordan . Uncorrected melting p oints were determined by using Hot -Stage, Gallen Kamp melting p oint apparatus .UV-Vis sp ectra of solution were p erformed on C ECL 7200 England Sp ectrop hotometer using CHCl3 as a solvent. S ynthesis methods Ethy l-4-Amino benzoate [I]: was p rep ared followin g the procedure by Vogel [13] , yield 99%, m.p.91 0 C, lit 91 0 C . COH2N O C2H5 [I] 4-amino phenyl hydrazide[II]: This comp ound was p repared accordin g to the let.[14] , y ield 99.5%, m.p. 223 0 C, lit 223 0 C. H2N C NH O NH2 [II] 5-(4-amino phenyl)-1,3,4-Oxadiazole-2-thiol [III]: This compound was p rep ared accordin g to the let. [15], y ield 79%, m.p . 239 0 C. IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 H2N NN O SH [III] n-alky l bromide[I V]n: was p repared following the procedure by Vo gel [13]. n=2,4,7 CnH2n+1Br [IV]n 2-alky l-thio-5-[4-amino phenyl ]-1,3,4-oxadiazole[V]: H2N NN O SCnH2n+1 n =2,4,7[V] Pot assium hy droxide (0.68g, 0.12mole) dissolved in minimum volume of water, was added drop wise to a stirred solution of oxadiazole (1.93 g , 0.01 mole) in (10mL) of dioxane at 25 0 C. Aft er heating the mixture for (15 min.) and cooling , n-alkyl bromid e (0.01mole) was add ed drop wise . The solution was refluxed for (2 hours) ; afterwards the solvent was evap orated on a rotator evap orator. Ice-water (100 mL) was added, the resulting p recipitate was collected [16] , and recry st allized from ethanol. Yield(85-92)% . symme trical ( N,N-pyromellitamic diacid)[VI]: NN O S, N S CO2H HO2C OC CO HN NH R R R= , N S n= [VI]a,b,c,n CnH2n+1 2,4,7; NN O SH , To a solution of py romellitic dianhy dride (0.218 g, 0.001mole) in (15mL) acetone, a solution of the amine (0.002 mole) in (15mL) acetone was added dropwise during on e hour, the mixture was then left at room temp erature with continuous stirring for (24 hours), t he product was then filtered off and recry st allized from acetone or chlorofor m. The p hy sical prop erties of these compounds are given in Table 1. IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 Sy mmetrical ( N,N-p y romellitdiimide)[ VII] NN O S, N S R= , N S n=CnH2n+1 2,4,7; NN O SH , a,b,c,n NN O O O O R R [VII] A(0.01 mole) of N,N-py romellitamic diacid was p laced in (250 mL) round bottom flask, a mixture of anhydrous sodium acetate ( 0.02mole ) and acetic anhydride (15mL) was added. The mixture was maintained between(85-90) ◦ C by means of a water -bath and st irred for half hour . The mixture was allowed to st ir for one hour at room temp erature . The mixture was p oured on dist illed water (400mL ) and worked out as sp ecified in each case. The physical data of diimides[ VII] are list ed in Table (2). Elemental analysis of compound [VII]7 : The oretical : C% = 62.82 , H% = 5.23 , N% = 10.99 Found : C% = 62.856 , H% =5.315 , N% =11.032 Carboxy lic Acid Chlorides [VIII]b,c: was p repared following the procedure by Vogel [13]. R-COCl [VIII] R = CnH2n +1 ;n =4,7 b, c N,N-Bis-[4-(2-thioacyl-1,3,4-oxadiazole-5-yl)-phenyl]-py romellitdiimid [IX]a- c NN NN O S C R O O O O R= C4H9 C7H15 OCH3 ,, [IX] O SCR O NN O To a stirred of compound [VII]C (0.568g, 0.001mol), triethy lamine (0.2g, 0.002mol) in dried mixture of (5ml DM F:10ml THF), was added dropwise carboxy lic acid chloride [VIII] (0.001mol) at (0-4) 0 C. Aft er the addition had been comp leted the resulting suspension was st irred at the same temp erature for 3hrs .The triethy laminhy drochloride salt was p recipitate . It was filtered and the filtrate was p oured with st irring into (100 mL) ice-water then the mixture was extracted by adding (50mL) of diethy l ether. Yield(77-90)% . IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 Result and Discussion Ethy l amino benzoate [I] was obtained from esterification of the carboxy lic acid moiety of 4-aminobenzoic acid by using absolute ethanol saturated with dry (HCI) gas .Condensation this ester [I] with hy drazide hy drate y ielded the 4-amino p henyl hy drazide [II] , which is characterization by higher meltin g p oint and by FT IR–sp ectrum , revealed st retching vibration at 3237 cm -1 of N-H group as well as st retching absorp tion at 1632 cm - 1 due to C=O (amid) group . The reaction of acid hy drazide[II] with CS2 in KOH medium leads to the formation of thio-oxadiazole [III] by intramoleculer cyclization r eaction . The st ructure of oxadiazole was confir med by meltin g p oint and by sp ectroscopy . The FTIR-absorption sp ectrum showed the disapp earance of absorp tion bands due to C=O (amid) and N-H group s of acid hy drazide together with the appearance of a st retching bands at 1630 cm -1 , 1308 cm -1 , 3102 cm -1 which are assigned to C=N, C=S and N-H group s, resp ectively of oxadiazole unit . It also shows stretching bands in the region (1050-1260)cm -1 due to (C-O-C) oxadiazole ring. 2-alky l-thio-5-[4-aminophenyl]-1,3,4-oxadiazole [V]n were p rep ared by the reaction of 2- mercap to-oxadiazole with differ ent n-alky l bromides in b asic medium. The st ructure of these comp ounds were identified by FTIR sp ectroscopy .The FT IR sp ectra of these comp ounds showed disappearance of the two p eaks attributed to N-H and C=S st retching and appearance of many p eaks in the region (2855-2967) cm -1 due to aliphatic C-H stretching. The amic acid [ VI] were sy nthesized by the reaction of one mole of p y romellitic dianhy dride with two moles of different amines in acetone as solvent. The mechanis m involves nucleop hilic addition reaction , as follows scheme (1). Scheme (1) OO O OO O NH2R Acetone C C C C N H H N O O R R H H C CO2HC HO2C HN NH O O R R R-NH2 Proton exchange [VI] O O O O The structure of these acids was studied by FTIR, UV-Vis and 1 HNM R sp ectroscopy . The FT IR absorp tion-sp ectra showed the disappearance of absorp tion bands due to NH2 and other p eaks characterized of cyclic anhydride of the st arting materials together with the appearance of new absorp tion st retching bands due to O-H of carbo xy lic moiety at (2500-3450)cm -1 , C=O (carboxy lic acid) at (1688-1716)cm -1 , C=O (amid) at (1645-1678)cm -1 and C=N (endocyclic) at (1609-1628)cm -1 of heterocyclic un it. The FTIR data of functional group s which are char acterist ic of the these new amic acid[VI]a- f and the UV-Vis data (λm ax) are list ed in Table 3. IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 1 HNM R sp ectrum of comp ound [VI]n=4 , showed the following characterist ic chemical shift ( DM SO as a solvent) : A triplet band at δ 1.40-1.45p p m due to terminal methy l p roton. Four p rotons mulitip let at δ 1.69-1.97pp m that could be related to -CH2CH2- p rotons and two p rotons triplet at δ 3.23-3.27pp m due to SCH2 . A sin glet sign al at δ 4.77pp m for p rotons of N-H, eight aromatic p rotons app ear as two doublets bands at δ 6.64-6.67pp m and δ7.58-7.61pp m. A good sharp sign al at δ 7.94 p p m due to the two p rotons of centre aromatic ring. Finally, two p rotons of carboxy lic moiety app ear as a broad weak band at δ 12.8-14.1pp m. Py romellitimides [VII]a- f were obtained by the intramolecular cyclization of amic acid [ VI]a- f in acetic anhydride and sodium acetate at 85 0 C. The mechanism involves nucleophilic substitut ion reaction as follows of scheme (2). NN O OO O C CO2HC HO2C HN NH O O R R CH3CO2 CH3CO2 C C C C NH HN O O R R H3C C O O C O CH3 C C O O HN NH O O R RC C H3C CH3 O O O O (80 -90)0 C RR Scheme (2) [VII] Na Na 2CH3CO2H H3C C O O C O CH3 O O O O NHNH O O O O O C CH3 O OCH3C O R R The structure of these comp ounds was st udied by FT IR, UV-Vis and 1 HNM R sp ectroscopy . The FT IR sp ectra exhibited si gnificant two p eaks in r egion (1700-1800) cm -1 which could be attributed to stretching vibration of the carbony l of the (imide cyclic) and two absorption bands around 1180cm -1 and 775cm -1 for asy m. and sy m. of C-N-C (cyclic). They also show t he disap p earance of absorp tion stretching bands of N-H , O-H and C=O (carboxy lic moiety ) group s of amic acid. The FTIR absorp tion bands data of these comp ounds[VII]a- f and the UV-Vis data (λm ax ) are list ed in Table (4). 1 HNM R sp ectrum of py romellitdiimide [ VII]c, (DM SO as a solvent) showed a good p eak at δ 2.69 p p m due to S-H group , eight aromatic p rotons of (AB) which are typical for p -disubstituted benzene appear as two doublets at δ 7.80-7.91 pp m [17] . A singlet signal at δ 7.95pp m for two p rotons of centre benzene ring and a sharp single at δ 10.38 pp m due to N-H group . Elemental analy sis result of comp ound [VII]7 is in good agreement with the theoretical data . N,N-Bis-[4-(2-thioacyl-1,3,4-oxadiazole-5-yl)-phenyl] py romellitdi-imid [IX]a- c sy nthesized by the reaction of [VII]c with acid chlor ide[ VIII]a- c in mixture of (DM F+THF) in the basic medium Et3N.T he FTIR sp ectra showed a good p eak at (1686-1715) cm -1 due to C=O thioester . The FTIR data of thioester [IX]a-c showed in Table 4. IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 Re ferences 1. Sharma ,P.; Kukreja , P.;Choudhary,V. and Naru la , A. (2005) "Curing and Thermal Behaviour of Epoxy Resin in The Presence of Oromatic I mide –Am ines", Ind. J. of Engin. and M at. Sci. of Chem., 12: 259-264. 2. Lee , S.;Shin,G.; Chi,J.; Zin,W.; Jung , J.;Hahm , S.; R ee , M . and Chang ,T. (2006) "Sy nthesis , characterization and liqu id-cry st al-aligning p rop erties of novel aromatic p olypy romellitimid es bearing (n-alkyloxy ) biphenyloxy side chains", Poly mer, 47: 6606-6621. 3. M athews , A.; Kim , I. and Ha ,C. (2007) " Sy nthesis, Characterization, and Prop erties of Fully Aliphatic Poly imides", M acromolecular R esearch, 15(2): 114-128. 4. Hoogenboom , R. and Schubert ,U. (2007) "M icrowave-Assisted Poly mer Sy nthesis : Recent Develop ments in a Rapidly Exp anding Field of Resear ch", M acromol. Rapid Commun., 28: 368–386. 5. Zheng ,Q.; Huan g ,J.; Sarjeant , A. and Howard, E. Katz (2008) "Py romellitic Di- imide M inimal Cores for Hi gh M obility ", J. AM . CHEM . SOC. 130: 410-411. 6. Darshan , M alhota , P. and Narula, K. (2009) "Effect of Structure of Diamide-Di- imide-Di amines Based on L-methionine on Curing Behavour and Thermal Stability of DGEBA", Ind. J. of Chem.,48B: 893-903. 7. M allakp our ,Sh. and Rafiee ,Z. (2008) "Ap p lication of M icrowave-assisted Reactions in Step-growt h Poly merization: A Review", Iran. Poly m. J.17(12):907-935. 8. Liu , P. (2005) "Prep aration and Characterizations of Poly (amic acid) Grafted Silica Nanop articles", Iran. Polym. J., l 14(11): 968-972. 9. Lucero, D.; Likh anova , N.; Hop fl , H.; Guz man , J.; Likhatchev, D. and Palou , R. ( 2006), " Efficient microwave-assist ed sy nthesis of bisimides", General Pap ers ARKIVOC,(x), 7-20. 10. Faghihi , K.; Shabanian , M . and Hajibevgi , M . (2009) "Optically Active and Organosoluble Poly (amide-imide)s Derived fro m N,N'-(Py romellitoy l)bis-L- histidine", M acromo. Res. ,17(11): 912-918. 11. Zahmatkesh , S. and Vakili , M . (2010) "Sy nthesis and Characterization of New Opt ically Active Poly (ethy l L-ly sinamide)s and Poly (ethy l L-ly sinimide)s", J. of Amino Acids ,1:1-6. IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 12. Sato,Y.; Yoshida , M . and Ando , S. (2006) "Optical Prop erties of Rod-like Fluorinated Poly imides and M odel Compounds Derived from Diamines havin g Hi gh Electro -donatin g Prop erties", J. of Phot op oly mer Sci. and Techno logy , 19(2): 297- 304. 13. A. I. Vo gel , Practical , (1974),"Organic Ch em., Longman Group Ltd.,Londdon, 3 rd Edition . 14. Atto, A.; M ohamed, M . and Hameed , A. (2000) " Sy nthesis , Sp ectroscopy and study of Some New 1,3,4-O xadiazole Derivatives, Iraq i J. Chem., 26(1) : 86-93. 15. Tomma , J.;Al-M ehdawy , M .; M ubbrik , S. and Al-Dujaili , A. (2004) "Sy nthesis Ant ibacterial Activity of Some New Sch iff Bases containing 1,3,4-Oxadiazole R ing", Iraqi J. Sci., 45(1) : 39-45. 16. Tomma , J. and Al-Dujili , A. (2002) "M esomorp hic Behaviour of Some New Schiff Base Est ers Containing 1,3,4-O xadiazole Unit ", 43(1): 35-57. 17. Tomma, j. (2001) " Sy nthesis Characterization and Investigation Effect of Chemical Const itution of Liquid-Cry stalline M onomers , Dimers and Polymers. Table (1) The physical propertie s of symmetrical diamic acid [VI]a-[VI]7 Co m.N o. Nomenclature Structural formula Molecular fo rmula M.P ◦C Yiel d% Color [VI] a N,N — -Bis-(2-thiazole)- pyromellitamic diacid CO 2 H HO2C N S N S HN NH O O C16H10N4O6S 2 >30 0 89 white [VI] b N,N — -Bis-(2- benzothiazol e) - pyromellitamic diacid. CO2H H O2C C C O NH O HN S N N S C24H14N4O6S 2 >30 0 91 white [VI] c N,N — -Bis-[4-(5-phenyl)- 2-thio-1,3, 4-oxadiazole - pyromellitamic diacid. CO2HC HO2C C O HN O NH NN O NN O HS SH C26H16N6O8S 2 >30 0 96 orang e [VI] 2 N,N — -Bis-[4-(2-ethylthio- 1,3, 4-oxadiazole-5-yl)- phenyl] pyromellitamic diacid. C CO 2 HC HO 2 C O O NH HN NN O NN O S SC 4H 9 C 4 H 9 C30H24N6O8S 2 >30 0 89 Orange [VI] 4 N,N — -Bis-[4-(2- butylthio-1,3,4- oxadiazole-5-yl)phenyl]- pyromellitamic diacid . CO2 H CO OC HO 2C HN NH NN O S C 4H 9 NN O SC4 H 9 C34H32N6O8S 2 276- 278 90 Orange [VI] 7 N,N — -Bis-[4-(2- heptylthio-1,3,4- oxadiazole-5-yl)-ph enyl]- pyromellitamic diacid. CO2 H HO2 C NN O SC7H15 NN O S C7HNH HN O O C40H44N6O8S 2 238 88 Yellow IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 Table (2):The physical propertie s of symmetrical pyromellitdiimide [VII]a-c ,n and [IX]a- c. Co m.N o. Nomenclature Structural formula Molecular fo rmula M.P◦ C Yiel d% Colo r [VII ]a N,N — -Bis-(2- thiazole)- pyromellitdiimide NN N S N S O O O O C16H6N4O4 S2 198- 200 78 Pale yellow [VII ]b N,N — -Bis-(2- benzothiazol e)- pyromellitdiimide NN N SS N O O OO C24H10N4O 4S2 >300 90 yellow [VII ]c N,N — -Bis-{[4-(2-thio- 1,3, 4-oxadiazole)-5- yl]-phenyl} – pyromellitdiimid. NN O O O O NN O HS NN O SH C26H12N6O 6S2 182- 184 92 Pale yellow [VII ]2 N,N — -Bis-[4-(2- ethylthio-1,3,4- oxadiazole-5-yl)- phen- yl] - pyromellitdiimide. NN NN O NN O SC2H5 C2H5S O OO O C30H20N6O 6S2 160- 162 85 orange [VII ]4 N,N — -Bis-[4-(2- butylthio-1,3,4- oxadiazole-5-yl) phenyl]- pyromellitdiimide. NN O O O O NN O NN O S S C4H9C4H9 C34H28N6O 6S2 138- 140 88 Pale yellow [VII ]7 N,N — -Bis-[4-(2- heptylthio-1,3,4- oxadiazole-5- yl)phenyl] - pyromellitdiimide NN NN O SC7H 15 O O O O NN O C7H15 C40H40N6O 6S2 92-94 75 Yello w [IX] a N,N-Bis-[4(2-thio-4- (methoxyphenyloxy- 5-yl)-phenyl]- pyromellitdiimide NN NN O NN O S S CC O O O O H3CO O CH3 OO C42H24N6O 10S2 oily 80 yellow [IX] b N,N-Bis-[4-(2-thio- pentyloxy-1,3,4- oxadiazole-5-yl)- phenyl ] - pyromellitdiimide NN NN O NN O S S CC C4H9C4H9 O O O O OO C36H28N6O 8S2 oily 77 Brown [IX] c N,N-Bis-[4(2-thio- heptyloxy-1,3,4- oxadiazole-5-yl)- phenyl ]- pyromellitdiimide NN NN O NN O S S CC C7H 15C7H15 O O O O O O C42H40N6O 8S2 Crysta l Gum my 90 yellow IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 Table(3):Characteristic FTIR a bsor ption bands and UV data (λmax) of compounds [ VI]a- Comp .No. λma (nm) V N- H VO-H VC-H aromatic VC-H aliphatic VC=O carboxylic VC= O amid VC=N endocyclic VC=C aromatic [VI]a 266 3302 3450- 2400 3113 1695 1659 1616 1580 [VI]b 264 3289 3200- 2450 3115 1688 1655 1628 1591 [VI]c 318 3352 3450- 2500 3103 1709 1678 1625 1607 [VI]2 306 3368 3400- 2400 3086 2967- 2855 1709 1670 1609 1587 [VI]4 300. 5 3350 3435- 2450 3077 2957- 2860 1716 1645 1609 1582 [VI]7 304 3348 3250- 2500 3075 2955- 2855 1710 1645 1609 1589 IBN AL- HAITHAM J. FOR PURE & APPL. S CI. VOL. 24 (3) 2011 Table(4):Characteristic FTIR a bsor ption bands and UV data (λmax) of compounds [VII]a-c ,n and [IX]a- c Com p.No. λmax(n m) VC-H arom. VC-H alipha. VC=O Imides Cyclic asym., sym VC=N endocycl ic VC=C aromati c VC-N-C asym., sym . Other [VII]a 268 3113 1800,1728 1685 1600 1172,779 [VII] b 250 3113 1787,1740 1634 1597 1195,772 [VII]c 302 3100 1728,1695 1622 1591 1180,760 VN-H at 3337 VC=S at 1317 [VII] 2 302.5 3100 2960- 2850 1740,1701 1605 1576 1179,775 [VII] 4 300 3110 2955- 2868 1736,1700 1607 1578 1182,765 [VII] 7 300 3051 2955- 2865 1740,1710 1601 1570 1175,768 [IX]a 310 3080 2959- 2859 1728,1700 1640 1606 1165,779 VC=0 thioester 1710 [IX]b 306.5 3100 2989- 2872 1724,1701 1645 1610 1175,780 VC=0 thioester 1715 [IX]c 315 3080 2959- 2872 1740,1710 1640 1607 1171,774 VC=0 thioester 1686 2011) 3( 24المجلد مجلة ابن الھیثم للعلوم الصرفة والتطبیقیة وحوامض یمیدثنائي اال لبایروملیتل تحضیر وتشخیص مشتقات جدیدة متماثلة االمیك لها جمبد هرمز توما ، العلیاوي كاظم ماذي الزم ، عماد تقي علي جامعة بغداد، ابن الهیثم-كلیة التربیة، قسم الكیمیاء 2011آذار 29 :استلم البحث في 2011آیار 30: قبل البحث في الخالصة من ثنائي انهدرید ، خطوتین يعن طریق تفاعل ذ [VII]یمید اال ةثنائی تمیلحضرت مركبات البایرو ةمختلف أمیناتحضرت حوامض االمیك الجدیدة من تفاعل ثنائي انهدرید البایرومیلیتك مع ، اذ المقابل البایرومیلیتك ضمني ال حلقيالغلق التضمن خطوة التفاعل الثاني بینما ت. "مذیبا ن الجافاالسیتو باستعمالتحتوي حلقة غیر متجانسة (90-80)حرارةوبدرجة خالت الصودیوم- حامض االمیك بوجود انهدرید الخلیك لجزیئة 0 C . -UV وأطیاف وتحلیل العناصر درجات انصهارها قیاس طةات صحة تراكیب المركبات المحضرة بوستاثب Vis 1 HNM R , FT IR : لها . حامض البایرمیلتامیك ,بایرومیلیتیك ثنائي االنهدرید , یمید ثنائي اال بایرومیلیت : الكلمات المفتاحیة