Denysenko O. Hetaryliden acetonitriles in the synthesis of vicinal heteroaromatic amino aldehydes

of Ukraine, Kyiv, 2021. The thesis is devoted to using hetarylidene acetonitriles of the benzimidazole and (benzo)thiazole series as available starting compounds in the synthesis of derivatives of heterocyclic vicinal amino aldehydes. Acylation of 2-(1,3-dimethyl-1,3-dihydro-2H-benzo[d]imidazol-2-ylidene)-acetonitrile and 2-(3-methylbenzo[d]thiazol-2(3H)-ylidene)acetonitrile with chloro-acetyl chloride proceeded smoothly, providing 2-(2,3-dihydro-1,3-dimethyl-benzimidazol-2-ylidene)- and 2-(3-methylbenzothiazol-2-ylidene)-4-chloro-3-oxobu-tanenitriles. The amination of 4-chlorobutanenitriles with substituted anilines gave the 2-(1-substituted-2-amino-4,5-dihydro-4-oxopyrrol-3-yl)-1,3-dimethylbenz-imida-zolium and -3-methylbenzothiazolium chlorides in high yields. The salts obtained were reduced with sodium borohydride to 4-(2,3-dihydro-1,3-dimethylbenzimidazol-2-yl)- and 4-(2,3-dihydro-3-methylbenzo-thiazol-2-yl)-1-substituted-5-aminopyrrol-3(2H)-ones. These pyrrole derivatives were shown to serve as synthetic equivalents of the corresponding 2-aminopyrrole-3-carboxaldehydes. Thus, their treatment with phenylhydrazine yielded 1-substituted 2-amino-4,5-dihydro-4-oxopyrrole-3-carboxaldehyde phenylhydrazones, whereas condensation with malonodinitrile afforded 1-substituted 6-amino-2,3-dihydro-3-oxopyrrolo[2,3-b]pyridine-5-carbonitriles.