Luminescent Gold(I) Carbenes from 2-Pyridylisocyanide Complexes: Structural Consequences of Intramolecular versus Intermolecular Hydrogen-Bonding Interactions
摘要:
Isocyanide [AuX(CNPy-2)] (X = Cl, C6F5, fluoromesityl, 1/2 octafluorobiphenyl) and carbene [AuX[C((NRR2)-R-1) (NHPy2)}] ((RRNH)-R-1-N-2 = primary or secondary amines or 1/2 primary diamine) gold(I) complexes have been synthesized and characterized. For X = Cl, the carbene complexes show aurophilic interactions. The fragment NHPy-2, formed in the carbenes, can give rise to intra- (for primary amines) or intermolecular (for secondary amines) hydrogen bonds, depending on the amine used. These bonds and contacts have been studied in the solid state and in solution. The intermolecular hydrogen bonds are split in an acetone solution, but the intramolecular ones, which close a six-membered ring, survive in solution. Except for the fluoromesityl derivatives, the carbene complexes display luminescent properties.
Enantioselective, Stereodivergent Hydroazidation and Hydroamination of Allenes Catalyzed by Acyclic Diaminocarbene (ADC) Gold(I) Complexes
作者:Dimitri A. Khrakovsky、Chuanzhou Tao、Miles W. Johnson、Richard T. Thornbury、Sophia L. Shevick、F. Dean Toste
DOI:10.1002/anie.201601550
日期:2016.5.10
The gold‐catalyzed enantioselective hydroazidation and hydroamination reactions of allenes are presented herein. ADC gold(I) catalysts derived from BINAM were critical for achieving high levels of enantioselectivity in both transformations. The sense of enantioinduction is reversed for the two different nucleophiles, allowing access to both enantiomers of the corresponding allylic amines using the
Parameterization of Acyclic Diaminocarbene Ligands Applied to a Gold(I)-Catalyzed Enantioselective Tandem Rearrangement/Cyclization
作者:Zachary L. Niemeyer、Suresh Pindi、Dimitri A. Khrakovsky、Christian N. Kuzniewski、Cynthia M. Hong、Leo A. Joyce、Matthew S. Sigman、F. Dean Toste
DOI:10.1021/jacs.7b08791
日期:2017.9.20
are developed in the context of a gold catalyzed enantioselectivetandem [3,3]-sigmatropic rearrangement-[2+2]-cyclization. Surrogate structures enable the rapid identification of parameters that reveal mechanistic characteristics. The observed selectivity trends are validated in a robust multivariate analysis facilitating the development of a highly enantioselective process.