Stereoselective Access to Tetra‐ and Tri‐Substituted Fluoro‐ and Chloro‐Borylalkenes via Boron‐Wittig Reaction
Seungcheol Han, Yeosan Lee, Yujin Jung, Seung Hwan Cho
Abstract
Reported herein is the efficient synthesis of tetra- and tri-substituted (Z)-fluoro- and (Z)-chloro-borylalkenes by the Boron-Wittig reaction of ketones and aldehydes with bench-top stable halo-diborylmethanes. The substrate scope is broad and the Boron-Wittig reaction proceeds from a diverse range of ketones and aldehydes including biologically relevant molecules with fluoro- or chloro-diborylmethanes, providing tetra- and tri-substituted (Z)-fluoro- and (Z)-chloro-borylalkenes in good yields with high stereoselectivity. The utilities of the obtained (Z)-fluoro- and (Z)-chloro-borylalkenes are highlighted by further modifications to afford fluoroalkene derivatives or all-carbon substituted alkene.