B(C6F5)3-Catalyzed Hydroarylation of Aryl Alkynes for the Synthesis of 1,1-Diaryl and Triaryl Substituted Alkenes

A new strategy for the synthesis of 1,1-diaryl and triarylsubstituted alkenes has been developed utilizing B(C6F5)(3)-catalyzed hydroarylation of alkynes with phenols. The method provides a direct route to ortho-alkenylated phenols with both terminal and internal alkynes. The reactions show excellent regioselectivity, and good stereoselectivity was observed for the hydroarylation of internal alkynes. Computational and experimental studies suggest that for the reaction of internal alkynes and phenols, an acid-catalyzed isomerization mechanism involving two tertiary carbonium ion intermediates is responsible for the formation of Z-triaryl substituted alkenes.

Automated summary

A new strategy has been developed for the synthesis of 1,1-diaryl and triarylsubstituted alkenes through B(C6F5)(3)-catalyzed hydroarylation of alkynes with phenols. The reactions exhibit excellent regioselectivity and good stereoselectivity, with computational and experimental studies suggesting an acid-catalyzed isomerization mechanism for the formation of Z-triaryl substituted alkenes from internal alkynes and phenols.