Palladium [ t -Bu (PCP)PdOH] Pincer Complex as a Catalyst in the Michael Reaction

High Resolution Image Download MS PowerPoint Slide The Michael reaction is a versatile carbon–carbon bond-forming strategy that is efficiently catalyzed by transition metal complexes. We report that the palladium [ t- Bu (PCP)PdOH] pincer complex effectively activates substrates and forms stable complexes with ketones. The reactive intermediate [ t- Bu (PCP)Pd(acac)] complex, which is formed in situ from acetylacetone and the [ t- Bu (PCP)PdOH] complex, was successfully isolated and structurally characterized by single-crystal X-ray diffraction. This complex serves as an active catalyst in the reaction between acetylacetone and various trans -nitrostyrenes, providing the corresponding Michael adducts in high isolated yields (87–98%). The reaction proceeds under mild conditions with a low catalyst loading, short reaction times, and often minimal or no solvent. These results show that PCP-palladium pincer complexes can serve as efficient, practical catalysts for C–C bond-forming condensation reactions.