Syn-SN2' Pathway in the Reaction of Certain γ-(Mesyloxy)α,β-Enoates with RCu(CN)MgX*BF3 Reagents. Importance of MgX and Bulky R Group upon the Diastereoselectivity

Article abstract of DOI:10.1021/jo00057a038

The reactions of protected serine- and threonine-derived γ-(mesyloxy)α,β-unsaturated esters with various magnesio organocyanocopper Lewis acid complexes have been investigated.The formation of syn-S_N2'products, in addition to the normally expected anti-S_N2'products, is taken as an indication that the reaction proceeds by a mechanism involving coordination of the magnesiocuprate with the C(δ)-N:C(γ)-O syn-γ-(mesyloxy) α,β-enoates.