Homolytic allylation of vinyl iodides with allylstananes

In the presence of AIBN or Et3B, a variety of vinyl iodides reacted with allylstannanes bearing an electron-withdrawing group at the β-position to afford 1,4-dienes in moderate to good yields. The allylation showed high stereoselectivity when the α-substituent of the iodides was a phenyl group, or the β-substituent was a bulky group.