A Facile Stereoselective Synthesis of (Z)-2-ethoxycarbonyl-substituted 1,3-enynes from (E)-α-stannyl-α,β-unsaturated esters and alkynyl bromides

Abstract

Palladium-catalysed hydrostannylation of alkynyl esters in benzene at room temperature gives regio- and stereoselectively ( E)-α-stannyl-α,β-unsaturated esters in good yields. ( E)-α-Stannyl-α,β-unsaturated ethyl esters are difunctional group reagents which undergo Stille coupling reactions with alkynyl bromides in the presence of Pd(PPh3)4 and Cul co-catalyst to afford stereoselectively ( Z)-2-ethoxycarbonyl-substituted 1,3-enynes in good yields.