Abstract Acylation of thiophene and phenol with 3, 4, 4-trichloro-3-butenoyl chloride afforded the corresponding 1-(thien-2-yl)-and 1-(4-hydroxyphenyl)-3, 4, 4-trichloro-3-buten-1-ones, whose reaction with amines led to the formation of 3-amino-1-(thien-2-yl, 4-hydroxyphenyl)- 4, 4-dichloro-2-buten-1-ones The heterocyclization of the initial ketones into pyrazole structure was not observed, and the reaction with hydrazine hydrate provided bispyrazole ...
