FeCl3·6H2O-catalyzed selective conjugate reduction of alkylidene-β-keto esters and alkylidene-1,3-diketones

Abstract

FeCl3·6H2O/triethylsilane composite catalyst system is successfully developed for the selective conjugate reduction of carbon-carbon double bond of Michael acceptor-alkylidene-β-keto esters and alkylidene-1,3-diketones under mild reaction conditions to afford the corresponding saturated β-keto esters and 1,3-diketones. The process involves the iron-catalyzed hydrosilylation, followed by in situ hydrolysis of silyl enol ether. The optimal reaction conditions include 20 mol% of FeCl3·6H2O and triethylsilane in dichloromethane at room temperature. A broad range of substrates undergoes the reduction in 1, 4-selective manner to afford the corresponding saturated compounds in excellent yields.