An Efficient CuI-Promoted Synthesis of Tri- and Tetrasubstituted Alkenes Using Organozinc Species

An efficient method for the synthesis of multifunctionalized alkenes has been developed. In the presence of 5 mol% CuI as catalyst, organozinc species CF3COOZnEt, CF3COOZnMe and CF3COOZnPh reacted with α,β-acetylenic ketones and aldehydes in one pot providing trisubstituted alkenes in high yields with stereoselectivity. The reaction with β-substituted-α,β-acetylenic ketones gave tetrasubstituted alkenes in good yields with Z-isomers as the major products.