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.
Asymmetric organocatalytic oxy-Michael addition of alcohols to α,β-unsaturated aldehydes
作者:Taichi Kano、Youhei Tanaka、Keiji Maruoka
DOI:10.1016/j.tet.2007.03.179
日期:2007.8
A 1,4-addition of alcohols to α,β-unsaturatedaldehydes was found to be efficiently promoted by biphenyldiamine-based catalyst 3 without formation of the acetals. An asymmetric variant of this reaction has also been performed by designing a novel axially chiral organocatalyst (R)-10c.
Catalytic enantioselective construction of all-carbon quaternary stereocenters by an organocatalytic Diels–Alder reaction of α-substituted α,β-unsaturated aldehydes
A binaphthyl-based primary amine (R)- was designed for the Diels-Alderreaction of alpha-substituted alpha,beta-unsaturated aldehydes; in the presence of the TfOH salt of (R)-, the Diels-Alderreaction of alpha-substituted alpha,beta-unsaturated aldehydes with cyclopentadiene proceeded to afford the corresponding cycloadducts having one all-carbon quaternary stereocenter in good yield with good to
Asymmetric Morita-Baylis-Hillman Reaction of Arylaldehydes with 2-Cyclohexen-1-one Catalyzed by Chiral Bis(Thio)urea and DABCO
作者:Min Shi、Xu-Guang Liu
DOI:10.1021/ol7028806
日期:2008.3.1
Novel bis(thio)urea organocatalysts were synthesized from axially chiral (R)-(-)-5,5',6,6',7,7',8,8'-octahydro-1,1'-binaphthyl-2,2'-diamine (H-8-BINAM), and their catalytic abilities have been examined in the Morita-Baylis-Hillman reaction of 2-cyclohexen-1-one or 2-cyclopenten-1-one with a wide range of aromatic aldehydes in combination with DABCO. The best result was achieved in the reaction of 3-fluorobenzaldehyde with 2-cyclohexen-1-one to give the desired Morita-Baylis-Hillman product in 79% yield and 88% ee.