Facial selectivity in nucleophilic reactions of spirocyclic ketones can be controlled by a distant, orthogonal double bond

Abstract

Spiro[4.5]dec-7-ene-1,4-dione and derivatives substituted at C-7, C-8, and/or C-9 gave products of reaction with methyllithium and with sodium borohydride that in every instance favoured nucleophilic carbonyl attack on the face syn to the double bond; the results are consistent with stereoelectronic control, and the selectivity correlates with a difference in the abilities of the orthogonal C–C bond to donate electron density.