Stereochemistry of Addition of Allylic Grignard Reagents to α,β-Ethylenic Ketones

Article abstract of DOI:10.1021/jo00062a009

The stereochemistry of the addition of allylic Grignard reagents, (mainly crotylmagnesium chloride) to various conjugated enones has been investigated and a compact transition state is postulated.For s-cis-enones bearing no bulky substituents, a boat transition state, involving a trans-crotylmagnesium chloride, occurs leading to erythro-1,5-hexadien-3-ols as the major or only product.