They discovered that using isopropyl magnesium bromide (i PrMgBr) as a base resulted in high (E)-selectivity, thanks to the formation of a magnesium phosphonoenolate intermediate.

(E)-Selective Weinreb Amide-Type Horner–Wadsworth–Emmons Reaction: Effect of Reaction Conditions, Substrate Scope, Isolation of a Reactive Magnesium Phosphonoenolate, and Applications.

The Horner–Wadsworth–Emmons (HWE) reaction is commonly used in organic chemistry to synthesize conjugated aldehydes. However, traditional HWE reaction methods sometimes have ...