摘要:
Acyl(phosphonato)palladium complexes, Pd(PMe3)2{C(O)Ph}{P(O)(OR)2} (R = Et (1a), Me (1b)), react with Et3OBF4 below room temperature at the phosphoryl oxygen to give cationic palladium phosphite complexes, [Pd(PMe3)2{C(O)Ph}{P(OEt)(OR)2}]BF4 (R = Et (2a), Me (2b)), in good yields, indicating that the phosphoryl oxygen in 1 is more nucleophilic than the benzoyl oxygen. The reaction of 1 with acid chlorides, R'C (0) Cl (R' = Ph, Me), proceeds rapidly even at 0-degrees-C to give Pd(PMe3)2(C(O)Ph}Cl and P(OR)2{OC(O)R'} with the Pd-C(O)Ph bond in 1 intact, and with facile Pd-P(O)(OR)2 bond cleavage. The reaction mechanism is discussed. Complex 1 shows no reaction with MeI (below 10-degrees-C) and with ketones (at room temperature). Complexes 1a and 2a were characterized by single-crystal X-ray diffraction analyses. Crystal data for 1a: space group P2(1), a = 11.966(3) angstrom, b = 9.619(2) angstrom, c = 10.462(3) angstrom, 0 = 101.72(2)-degrees, Z = 2, 2699 reflections, R = 0.038. Crystal data for 2a: space group P1BAR, a = 10.782(2) angstrom, b = 10.820(2) A, c = 13.255(2) angstrom, alpha = 84.20(1)-degrees, beta = 79.39(1)-degrees, gamma = 69.94(1)-degrees, Z = 2,5518 reflections, R = 0.045.