Allylstannylation of Carbon−Carbon and Carbon−Oxygen Unsaturated Bonds via a Radical Chain Process1

Abstract

In the presence of a radical initiator, allyltributylstannanes bearing an electron-withdrawing group at the beta-position smoothly reacted with electron-deficient terminal alkenes to give allylstannylated products in good yields. The stannyl group was introduced into the terminal carbon with high regioselectivity. The allylstannylation of homochiral 8-phenylmenthyl acrylate proceeded with moderate to good diastereoselectivity. Terminal and electron-deficient internal alkynes as well efficiently underwent the radical-initiated allylstannylation in an anti addition mode. The reaction of terminal alkynes showed the same regioselectivity as that of terminal alkenes. The present radical reaction was applicable to allylation of aromatic aldehydes and ketones.