Reductive Conjugate Addition of Haloalkanes to Enones To Form Silyl Enol Ethers

Weix, D., and R. Shrestha. Reductive Conjugate Addition of Haloalkanes to Enones To Form Silyl Enol Ethers. Org. Lett., 2769.
Abstract A new method is presented for tandem reductive conjugate addition and silyl enol ether formation from cyclic and acyclic enones and enals in the presence of a Mn reductant, a Ni(terpyridine) catalyst, and a trialkylchlorosilane. The addition of secondary, tertiary, and hindered primary haloalkanes Is demonstrated. Preliminary studies on the mechanism show that the intermediacy of L1(Ni)(eta(3)-1-triethylsilyloxyalkenyl)X or in-situ-formed RMnX is unlikely.
Keywords activated olefinsalkyl-halidesallylic grignard-reagentsaryl halidesbicyclic ketonescarbonyl-compoundscobaltcross-coupling reactionsnickel-complexesorganic halides
DOI 10.1021/ol200881v