Thesis (M.Sc.) - Cairo University - Faculty of Science - Department of Organic Chemistry

English summary The present thesis outlines the utility of C-alkyl hydrazonoyl bromide in the synthesis of heterocyclic compounds. The first part of the thesis concerned with the synthesis of new thia- and selena- diazoles and 1,2,9-triazaspiro[4.4]non-2-en-8-ones. Treatment of a mixture of thioanilides 3a-f and N-(4-nitrophenyl)propionohydrazonoyl bromide 1 in refluxing chloroform with triethylamine afforded the corresponding thiadiazoles 6a-f (Scheme 1). Stirring of compound 10 with N-(4-nitrophenyl)propionohydrazonoyl bromide 1 in absolute ethanol in the presence of triethylamine at room temperature afforded the corresponding thiadiazole 15 (Scheme 2). In a similar manner, compound 1 reacted with methyl 2-((1,5-dimethyl-3-oxo-2-phenyl- 2,3-dihydro-1H-pyrazol-4-yl)methylene)hydrazine-1-carbodithioate 16 and methyl 2-((1,3- diphenyl-1H-pyrazol-4-yl)methylene)hydrazine-1-carbodithioate 17 in absolute ethanol in the presence of triethylamine to yield 4-((5-ethyl-3-(4-nitrophenyl)-1,3,4-thiadiazol-2(3H)-ylidene)- hydrazono)methyl)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one 18 and 2-((1,3- diphenyl-1H-pyrazol-4-yl)methylene)hydrazono)-5-ethyl-3-(4-nitrophenyl)-2,3-dihydro-1,3,4- thiadiazole 19, respectively (Scheme 3). Also, methyl cyclocarbodithioates 20-23 were treated with N-(4-nitrophenyl)- propionohydrazonoyl bromide 1 in ethanolic triethylamine solution to afford the corresponding 1,3,4-thiadiazole 24-27 (Scheme 4).

Issued also as CD