Synthesis and Reactions of Silylated and Stannylated 1,2-Azoles
作者:Mariola Calle、Purificación Cuadrado、Ana M. González-Nogal、Raquel Valero
DOI:10.1055/s-2001-17699
日期:——
Silicon or tin 4-metalated pyrazoles and isoxazoles are synthesized by silyl- or stannylcupration from 4-haloazoles. On the other hand, 5-metalated pyrazoles are prepared by reaction of 5-unsubstituted pyrazoles with LDA and subsequent treatment with chlorosilanes and chlorostannanes. Furthermore, starting from 5-unsubstituted 4-halopyrazoles and applying both methodologies, 4,5-dimetalated pyrazoles bearing silyl groups different from trimethylsilyl or tributylstannyl groups are obtained. Some regioselective ipso-substitutions are also studied.