Palladium-Catalyzed Dehydrative Cross Couplings of Stabilized Phosphorus Ylides with Allylic Alcohols

A dehydrative cross coupling of ketone-stabilized phosphorus ylides with the readily available allylic alcohols followed by an one-pot Wittig reaction is developed. A range of functional 1,4-dienes could be obtained in 52%similar to 95% isolated yields in the presence of 5 mol% Pd(PPh3)(4) and 20 mol% B(OH)(3). The same method can be extended to ester or nitrile-stabilized phosphorus ylides, affording the corresponding 1,4-dienes in moderate yields.