Complete control of the face of attack in the addition of stannylmetal reagents to γ-alkoxy-α,β-unsaturated esters can be achieved by using the appropriate counterion (see scheme). The stereochemistry of addition does not depend on the configuration of the C-C double bond, although the stereoselectivity is consistently better with the Z stereoisomer, for which 100% Si attack is obtained with Li as counterion and 100% Re attack with LiZnEt.
|Number of pages||3|
|Journal||Angewandte Chemie. International edition|
|Publication status||Published - 12 Jul 1999|
Krief, A., Provins, L., & Dumont, W. (1999). Metal-mediated, completely diastereofacial conjugate addition of trialkylstannylmetal reagents to γ-alkoxy-α,β-unsaturated esters. Angewandte Chemie. International edition, 38(13-14), 1946-1948.