COORDINATIVELY INDUCED 1,4-DIASTEREOSELECTION IN THE REACTION OF ACYCLIC α,β-ENONES WITH ORGANOCOPPER REAGENTS. A NEW TYPE OF ORGANOCOPPER REAGENT

Article abstract of DOI:10.1016/0040-4020(89)80082-1

A test has been made of a stereochemical prediction for conjugate addition based on the intermediacy of d,?*-complexes in the reaction of organocopper reagents with α,β-enones.The chiral α,β-enone 7 has been synthesized and subjected to reaction with various methyl cuprate reagents.Under conditions favorable to lithium chelation to the α-alkoxycarbonyl system of 7, conjugate addition to 7 was found to proceed with high (13:1 to 33:1) 1,4-diastereoselectivity, the configuration of the major diastereomer being that predicted by the d,?*-complex model.A new and especially diastereoselective reagent has been generated by the reaction of LiCuMe2 with 0.3 equivalent of water, a possible structure for which is presented.