Quinidine derivative (QD)2PYR was found to catalyze the asymmetric direct amination of unprotected prochiral 3-oxindole with DIAD to construct quaternary stereocenters at the C3 position with excellent enantioselectivity.
Nickel Catalyzed Alkylation of Oxindoles with Alkyl Alcohols
作者:Adrija Ghosh、Atanu Bera、Debasis Banerjee
DOI:10.1002/cctc.202201433
日期:2023.2.20
Alkylation with alcohols: Herein, nickel-catalyzed hydrogen borrowing strategy was employed for alkylation of 2-oxindoles using alkyl alcohols. Initial mechanisticstudies, deuterium labelling experiments and late stage synthetic modulation of the alkylated products were performed.
A Bench‐stable 8‐Aminoquinoline Derived Phosphine‐free Manganese (I)‐Catalyst for Environmentally Benign C(α)‐Alkylation of Oxindoles with Secondary and Primary Alcohols
作者:Parul Saini、Pritam Dolui、Abhishek Nair、Ashutosh Verma、Anil J. Elias
DOI:10.1002/asia.202201148
日期:2023.3.14
air-stable, phosphine-free 8-aminoqunoline (8-AQ) based Mn(I) carbonyl complex as the catalyst for the C(α)-alkylation of oxindoles with alcohols has been developed. The Mn complex [(8-AQ)Mn(CO)3Br] works effectively as a catalyst for α-alkylation of oxindoles by both secondary as well as primary alcohols. Few pharmaceutically relevant compounds were also synthesized by this method in good yields.
PyBroP-mediated nucleophilic addition of oxindoles with pyridine N-oxides to access 3-pyridyl-3,3-disubstituted oxindoles
作者:Fuzhong Han、Wenjia Xiao、Lina Jia、Xiangping Hu
DOI:10.1039/d3nj04907h
日期:——
A sustainable and efficient strategy for the synthesis of 3-pyridyl-3,3-disubstituted oxindole derivatives has been achieved via PyBroP (bromotripyrrolidinophosphonium hexafluorophosphate) promoted nucleophilic addition reaction of oxindoles with pyridine N-oxides. The approach worked well under relatively mild conditions. The protocol features a broad substrate scope and good functional group tolerance
artificial catalysts for asymmetric synthesis. Polyfunctional catalysts are considered to be a promising tool for achieving excellent catalytic efficiency. A polyfunctional catalyst system was developed, which incorporates two Lewisacidic/Brønsted basic cobalt centers in combination with triazolium moieties that are crucial for high reactivity and excellent stereoselectivity in the direct1,4‐addition of