Synthesis of β-Amino and β-Methoxy Ketones by Lewis Acids Promoted β-Substitution Reactions of β,γ-Unsaturated Ketones

Abstract

A reaction mixture of β,γ-unsaturated ketone and BF 3 .OEt 2 in CH 3 OH was stirred at room temperature and β-methoxy ketone was produced in high yield. The β-amino ketone was obtained as the major product from a reaction mixture of β,γ-unsaturated ketone, AlCl 3 and Ts-NH 2 in CH 2 Cl 2 at room temperature. This Lewis acid promoted β-substitution reaction mechanism was proposed as that the process occurred via in situ isomerization of β,γ-unsaturated ketone to α,β-unsaturated ketone followed by the 1,4-addition reaction.