الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In this work we were Synthesis some new benzimidazoles derivatives and study of their electrochemical behaviour. Firstily synthesis and reaction of 2-amino-4-(1H-benzimidazol-2-ylmethyl)-thiazole(3) was prepared via condensation of 2-(bromoacetonyl)-1H-benzimidazole (2) with thiourea. Reaction of 3 with carbon disulfide to yield thiosemicarbazidederivative 4 which react with acetyl chloride and benzoyl chloride respectively to give 5-(methyl or phenyl)-2H-1, 2, 4-triazole-3(4H)-thionederivatives 5a, b. The reaction of 3 with arylidene compounds to givevarious pyrimidine derivatives 6-7. The reaction of ammonium thiocynate with 3 followedbyreaction with ethyl cyanoacetate to give 2-thioxo-pyrimidin-4-one 9. Diazotized of 3 coupled with β-napthol to yield diazo derivative 10. The reaction of 3 with ethyl cynoacetate to give pyrimidin-7-one derivative 11.
4-Amino-5-(1H-benzimidazol-2-yl)-6-(4-chlorophenyl)pyridine-3-carbonitrile (14) was obtained from reaction of 2-cyanomethyl-1H-benzimidazole (12) with chlorobenzaldehyde followed by reaction with malononitrile. Reaction of 14 with cyclohexanone, formic acid and hydrazine hydrate afforded tetrahydrobenzonaphthyridine amine, pyrido[4,3-d]pyrimidin-4(3H)one and pyrazolo[4,3-c]pyridine-3-amine 15-17 respectively.Heterocyclization of 14 with carbon disulfide and benzoylisothiocyante gave the corresponding pyrido[3,4-d]pyrimidindithione and thioxopyrido[4,3-d]pyrimidine methanone 18 and 19. While, the reaction of 14 with active methylene group named ethyl cyanoacetate, diethyl malonate and with nitrous acid afforded oxo-1,6-naphthyridin-3-carbonitrile, carboxylate and pyrido[4,3-d][1,2,3]triazine 20-22 respectively.Dihydroimidazolpyridin-4-amine 23 was obtained from reaction of 14 with ethylendiamine and carbon disulfide. Finally, treatment of 14 with triethylorthoformate underwent cyclization in the presence of hydrazine hydrate afforded pyrido[4,3-d]pyrimidin-3-ylamine 25.The newly synthesized compound elucidated by IR, 1HNMR and elemental analysis.
Compounds (6b, 7, 15, 19, 20, and 25) were extensively studied using cyclic voltammetry to obtain number of electrons participating in each redox process. Show cyclic voltammetry of the investigated compounds on stationary Pt- electrode in dimethyl formamide with 0.1 mol potassium perchlorate as supporting electrolyte at 25 oC. The potential of the working electrode is measured against Ag/Ag+ electrode.