Amine‐ and Sulfonamide‐Promoted Wittig Olefination Reactions in Water

Amine-promoted olefination: The reaction of a phosphonium salt and an aldehyde in water to yield alkenes with high E-configurational control is promoted by catalytic amounts of non-basic amines in aqueous bicarbonate media. Possible catalytic cycles involving imines and iminium intermediates are discussed.