Aqueous Wittig reactions of semi-stabilized ylides. A straightforward synthesis of 1,3-dienes and 1,3,5-trienes

A direct synthesis of 1,3-dienes and 1,3,5-trienes from the reaction of semi-stabilized ylides and a range of saturated and unsaturated aldehydes is reported in water as solvent, employing sodium hydroxide as base. The water-soluble phosphine oxide side product is removed simply by aqueous partitioning of the organic products.