Tandem Au-Catalyzed 3,3-Rearrangement−[2 + 2] Cycloadditions of Propargylic Esters: Expeditious Access to Highly Functionalized 2,3-Indoline-Fused Cyclobutanes
摘要:
The treatment of readily available propargylic indole-3-acetates with a catalytic amount of AuCl(PPh3)/AgSbF6 leads to tandem activations of the propargylic esters and the in situ generated allenylic esters, resulting in expeditious access to highly functionalized cyclobutanes with fused 2,3-indoline and gamma-lactone rings and an exocyclic E-double bond through sequential 3,3-rearrangement and [2 + 2] cyclization.
Tandem Au-Catalyzed 3,3-Rearrangement−[2 + 2] Cycloadditions of Propargylic Esters: Expeditious Access to Highly Functionalized 2,3-Indoline-Fused Cyclobutanes
摘要:
The treatment of readily available propargylic indole-3-acetates with a catalytic amount of AuCl(PPh3)/AgSbF6 leads to tandem activations of the propargylic esters and the in situ generated allenylic esters, resulting in expeditious access to highly functionalized cyclobutanes with fused 2,3-indoline and gamma-lactone rings and an exocyclic E-double bond through sequential 3,3-rearrangement and [2 + 2] cyclization.
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.
Gold Catalysis, Asymmetric Friedel–Crafts Alkylation Cascade for One-Pot Synthesis of Chiral Dihydrocarbazoles and Dihydrodibenzofurans
作者:Xuan Wang、Ai-Hua Zhou、Tian-Qi Hu、Zhou Xu、Bo Zhou、Long-Wu Ye
DOI:10.1021/acs.orglett.4c00311
日期:2024.3.15
A one-pot gold-catalyzed acylmigration followed by ytterbium-catalyzed asymmetric Friedel–Crafts alkylation is disclosed, leading to the rapid synthesis of chiral dihydrocarbazoles and dihydrodibenzofuran in generally moderate to good overall yields with good to excellent enantioselectivities. The gold-catalyzed acylmigration of propargyl acetates generates α-ylidene-β-diketones with high E/Z ratios