The photoreaction of 1-aryl-2,2-dicyanoethenes with allylic silanes in the presence of phenanthrene gave 4-aryl-5,5-dicyano-1-pentenes in high yields. In this photoreaction, the allylic groups were introduced regioselectively at the β-position to cyano group. In contrast, the photoreaction of alkylidenepropanedinitriles with allylic silanes gave products allylated at the α-position to cyano group along with their reduction products.
1-芳基-2,2-二
氰基
乙烯与烯丙基
硅烷在
菲存在下进行光反应,以高产率生成4-芳基-5,5-二
氰基-1-
戊烯。在该光反应中,烯丙基被区域选择性地引入
氰基的β位。相反,亚烷基
丙二腈与烯丙基
硅烷的光反应得到在α位上烯丙基化为
氰基的产物及其还原产物。