Regioselective Cis Insertion of DMAD into Au–P Bonds: Effect of Auxiliary Ligands on the Reaction Mechanism
摘要:
The cis insertion of dimethyl acetylenedicarboxylate (DMAD, 2) into the Au-P bond of Au(SAr)(PAr'3) (1) occurs selectively at room temperature to give adduct 3, whose X-ray crystallographic analysis exhibits the predominant character of an alkenylphosphorus zwitterion complex. The first-order kinetics with respect to 1 and 2 and the large negative value of Delta S-double dagger indicate that the reaction proceeds through the coordination of 2 to 1 followed by a concerted inner-sphere nucleophilic attack of PPh3 on the coordinated triple bond. In contrast, Au(Cl)(PPh3) (4) does not react with 2 even at 60 degrees C. However, the tricoordinated 16-electron complex Au(Cl)(PPh3)(2) (5) quite successfully reacts with 2 to produce insertion product 6, demonstrating that two PPh3 ligands are required for the reaction.
The influence of gold(<scp>i</scp>) on the mechanism of thiolate, disulfide exchange
作者:Gamage S. P. Garusinghe、S. Max Bessey、Alice E. Bruce、Mitchell R. M. Bruce
DOI:10.1039/c6dt01400c
日期:——
The mechanism of gold(I)-thiolate, disulfide exchange was investigated by using initial-rate kinetic studies, 2D (1H–1H) ROESY NMR spectroscopy, and electrochemical/chemical techniques. The rate law for exchange is overall second order, first order in gold(I)-thiolate and disulfide. 2D NMR experiments show evidence of association between gold(I)-thiolate and disulfide. Electrochemical/chemical investigations
Mono and dinuclear gold(I) complexes with neutral and deprotonated 1,4-benzodiazepin-2-ones. Crystal and molecular structure of (L-H)Au(PPh3)·Et2O, where L = 1,3-dihydro-7-nitro-5-phenyl-2H-1,4-benzodiazepin-2-one, nitrazepam
作者:Maria Agostina Cinellu、Sergio Stoccoro、Giovanni Minghetti、Anna Laura Bandini、Francesco Demartin
作者:Narayanaswamy, Ratnavathany、Young, Michelle A.、Parkhurst, Erica、Ouellette, Michelle、Kerr, Margaret E.、Ho, Douglas M.、Elder, Richard C.、Bruce, Alice E.、Bruce, Mitchell R. M.