Synthesis of some 1‐substituted‐3‐or‐5‐styrylpyrazoles

Abstract

The synthesis of the title compounds by the Wittig‐Horner reaction is described, using the 3‐or‐5‐hydroxymethylpyrazole derivatives as precursors.

Styrylpyrazoles: Properties, Synthesis and Transformations

“…Deshayes et al reported the reaction of phosponic esters, prepared from 1-substituted 5-bromomethylpyrazoles 105 and triethyl phosphite, with substituted benzaldehydes and furfural, in dimethoxyethane, as a method to prepare ( E )-4-ethoxycarbonyl-3-methyl-5-styryl-l-substituted pyrazoles 106 ( Scheme 32 ) [ 75 , 85 ].…”

“…Molecules 2020, 25, x FOR PEER REVIEWDeshayes et al reported the use of 3-bromomethylpyrazole 54 as template for the synthesis of (E)-3-styrylpyrazole 55. In a first step, this compound was treated with triethyl phosphite, in the Arbusov reaction, affording the corresponding diethylphosphonomethylpyrazole, which then reacted with benzaldehyde in the presence of sodium hydride to give the corresponding (E)-3-styrylpyrazole 55 (Scheme 15)[75].Molecules 2020, 25, x FOR PEER REVIEW 13 of Synthesis of (E)-3-styrylpyrazole 55[75].…”