Facile and selective deallylation of allyl ethers using diphosphinidenecyclobutene-coordinated palladium catalysts

(π-Allyl)palladium triflate bearing a 1,2-bis(4-methoxyphenyl)-3,4-bis(2,4,6-tri-tert-butylphenylphosphinidene)cyclobutene ligand (DPCB-OMe), [Pd(η3-C3H5)(DPCB-OMe)]OTf, efficiently catalyzes deallylation of a variety of allyl ethers in aniline to give corresponding alcohols in high yields under mild conditions. The reactions can be performed in air without loss of a variety of functionalities including vinyl, alkynyl, hydroxy, acetoxy, silyloxy, and acetal groups. Allyl 2-allyloxybenzoate selectively undergoes deallylation of the allyloxy group to give allyl salicylate in quantitative yield.