

REACTION OF 3-[(ALKYLSULFANYL)METHYL]PENTANE-2,4-DIONES WITH NICOTINIC HYDRAZIDE

Abstract
The reaction of 3-[(alkylsulfanyl)methyl]pentane-2,4-diones with nicotinic hydrazide in ethanol as solvent produces 4-[(alkylsulfanyl)methyl]-substituted 1-(pyridin-3-yl)carbonyl-1H-pyrazoles, whereas 1-acyl-1H-pyrazoles are formed in acetic, propanoic, or pentanoic acid solution. The reaction in methanol in the presence of ZnCl2 is accompanied by elimination of nicotinic acid and the formation of (alkylsulfanyl)methyl-substituted 1H-pyrazoles.
Keywords
1-acyl-1H-pyrazole; 3-[(alkylsulfanyl)methyl]pentane-2,4-dione; nicotinic hydrazide; 1-(pyridin-3-yl)carbonyl-1H-pyrazole; heterocyclization.
Latvian Institute of Organic Synthesis - Aizkraukles iela, 21, Riga, LV-1006, Latvia - hgs@osi.lv