Synthesis and reactivity of cationic palladium phosphine carboxylate complexes

Simple routes to two new types of mononuclear cationic palladium phosphine acetate complexes featuring K-1- or K-2-carboxylates have been developed, and the resulting materials have been characterized by single-crystal X-ray diffraction. In acetonitrile the complex [((Pr3P)-Pr-i)(2)Pd((KO)-O-2,O'-OAc)](+) leads not to the independently prepared trans-[((Pr3P)-Pr-i)(2)Pd(MeCN)(OAc)](+) but to reversible cyclometalation to form [((Pr3P)-Pr-i)(MeCN)Pd((KC)-C-2,P-C(Me)(2)(PPr2)-Pr-i)](+).