

AQUEOUS N-METHYLMORPHOLINE N-OXIDE AS A NEW MEDIUM FOR ALKYLATION OF PYRAZOLES

Abstract
It is shown that alkylation of pyrazoles with (E)/(Z)-1,3-dichlorobut-2-enes can be carried out in an alkaline aqueous medium in the presence of N-methylmorpholine N-oxide. In some cases, this technique may substitute phase-transfer catalysis. Conformational analysis of the reaction products showed that a mixture of (E)/(Z) isomers is formed in a ratio of 9:1.
Keywords
1,3-dichlorobut-2-ene, N-methylmorpholine N-oxide, pyrazole, alternative reaction medium, phase-transfer catalysis.
Latvian Institute of Organic Synthesis - Aizkraukles iela, 21, Riga, LV-1006, Latvia - hgs@osi.lv