Magnesium-alkoxide directed photoaddition of tetrahydrofurans to gamma,gamma-disubstituted allylic alcohols was achieved. When the allylic alcohols were treated with Grignard reagent in THF under light, the corresponding gamma-(2-tetrahydrofuryl) substituted alcohols were regioselectively obtained in up to 82% yield. The conversion of the hydroxyl group to the corresponding bromomagnesium alkoxide was crucial.