Selective alkylation of aldehydes by allyl bromide and tin

It has been reported that allylic organotin compounds,such as tributylcrotyl tin,reactedwith carbonyl compounds to give correspon djng homoallyl alcohols.It was also foundthat allyl bromide and tin powder jn tetrahydrofuran(THF)can be directly used in this reac-tion,and a small amount Of water seems to be accelerating.In this paper we report thedirect,selective allylation of aldehydes which contain hydroxy,phenolic hydroxy,aromaticnitro,bromo or alkylketo group by allyl bromide and powdered tin,without the protection