Synthesis of 3,5-Disubstituted Pyrazoles via Cope-Type Hydroamination of 1,3-Dialkynes
摘要:
An efficient method for the synthesis of 3,5-disubstituted pyrazoles is described. The reactions of 1,3-dialkynes with hydrazine proceeded smoothly in dimethyl sulfoxide under mild reaction conditions to produce 3,5-disubstituted pyrazoles in satisfactory to excellent yields. A one-pot procedure of the transformation has been developed.
Continuous-flow synthesis of 3,5-disubstituted pyrazoles <i>via</i> sequential alkyne homocoupling and Cope-type hydroamination
作者:Sándor B. Ötvös、Ádám Georgiádes、Dániel Ozsvár、Ferenc Fülöp
DOI:10.1039/c9ra01590f
日期:——
A flow chemistry-based approach is presented for the synthesis of 3,5-disubstituted pyrazoles via sequential copper-mediated alkyne homocoupling and Cope-type hydroamination of the intermediary 1,3-diynes in the presence of hydrazine as nucleophilic reaction partner. The proposed multistep methodology offers an easy and direct access to valuable pyrazoles from cheap and readily available starting materials