Use of Silver Carbonate in the Wittig Reaction

An
efficient synthesis of olefins by the coupling of stabilized,
semistabilized, and nonstabilized phosphorus ylides with various carbonyl
compounds in the presence of silver carbonate is reported. Wittig
olefination of aromatic, heteroaromatic, and aliphatic aldehydes (yields
>63%) and a ketone (yield 42%) are demonstrated. These reactions
proceed
overnight at room temperature, under weakly basic conditions, and
as such extend the applicability of the Wittig reaction to base-sensitive
reactants.