A gold-catalyzedoxidation of arylallenes to form alpha-diketones and aldehydes in good yields is presented. Further directed synthesis of quinoxalines and benzimidazoles, via the condensation of the resulting alpha-diketones and aldehydes with benzene-1,2-diamine, was achieved in high yields.
Nickel-Catalyzed Asymmetric Hydrocyanation of Allenes
作者:Jinguo Long、Jihui Gao、Xianjie Fang
DOI:10.1021/acs.orglett.9b03938
日期:2020.1.17
The first catalytic enantioselective hydrocyanation of allenes catalyzed by a (R,R)-Ph-BPE-Ni(0) complex catalyst has been accomplished. Numerous optically active allylic nitriles were obtained in good yield with excellent enantioselectivities (up to 98% ee).
Gold-catalyzed intermolecular hydroamination of allenes with sulfonamides
作者:Chen Zhang、Shao-Qiao Zhang、Hua-Jun Cai、Dong-Mei Cui
DOI:10.3762/bjoc.9.117
日期:——
A co-catalyst of (PPh3)AuCl/AgOTf for the intermolecularhydroamination of allenes with sulfonamides is shown. The reaction proceeded smoothly under mild conditions for differently substituted allenes giving N-allylic sulfonamides in good yields with high regioselectivity and E-selectivity.
The highlyselective copper‐catalyzed hydroboration of allenes has been developed. Allylboranes and alkenylboranes were selectively prepared by the judicious choice of catalytic species (copper hydride and boryl copper). Furthermore, two types of alkenylboranes could be selectively synthesized by the choice of an appropriate ligand. Mechanistic studies confirmed that the protonation of a (Z)‐σ‐allyl
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