Carbene‐Catalyzed Enantioselective Aromatic N‐Nucleophilic Addition of Heteroarenes to Ketones
作者:Yonggui Liu、Guoyong Luo、Xing Yang、Shichun Jiang、Wei Xue、Yonggui Robin Chi、Zhichao Jin
DOI:10.1002/anie.201912160
日期:2020.1.2
and optical purities. Our reaction involves the formation of an unprecedented aza-fulvene-type acylazolium intermediate. A broad range of N-heteroaromatic aldehydes and electron-deficient ketone substrates works effectively in this transformation. Several of the chiral N,O-acetal products afforded through this protocol exhibit excellent antibacterial activities against Ralstonia solanacearum (Rs) and
Carbene‐Catalyzed Enantioselective Aldol Reaction: Post‐Aldol Stereochemistry Control and Formation of Quaternary Stereogenic Centers
作者:Xing Yang、Pankaj Kumar Majhi、Huifang Chai、Bin Liu、Jun Sun、Ting Liu、Yonggui Liu、Liejin Zhou、Jun Xu、Jiawei Liu、Dongdong Wang、Yanli Zhao、Zhichao Jin、Yonggui Robin Chi
DOI:10.1002/anie.202008369
日期:2021.1.4
The dominated approaches for asymmetric aldol reactions have primarily focused on the aldol carbon–carbon bond‐forming events. Here we postulate and develop a new catalytic strategy that seeks to modulate the reaction thermodynamics and control the product enantioselectivities via post‐aldol processes. Specifically, an NHC catalyst is used to activate a masked enolate substrate (vinyl carbonate) to
Enantioselective Alkynylation of Isatin Derivatives Using a Chiral Phase-Transfer/Transition-Metal Hybrid Catalyst System
作者:Suva Paria、Hyo-Jun Lee、Keiji Maruoka
DOI:10.1021/acscatal.8b04949
日期:2019.3.1
An enantioselective alkynylation of isatin derivatives can be realized by using a hybrid catalyst system consisting of chiral phase-transfer catalyst and transition-metal catalyst. The chiral alkynylation products can be used as versatile intermediates for further synthetic transformations.
Copper-catalyzed asymmetric addition of arylboronates to isatins: a catalytic cycle involving alkoxocopper intermediates
作者:Ryo Shintani、Keishi Takatsu、Tamio Hayashi
DOI:10.1039/c0cc01635g
日期:——
A copper-catalyzedaddition of arylboronates to isatins has been developed to give 3-aryl-3-hydroxy-2-oxindoles under mild conditions. The catalytic cycle of this process has been examined through a series of stoichiometric reactions and an effective asymmetric variant has also been described by the use of a chiral N-heterocyclic carbene ligand.
Get selective! Enantioselective allylation of ketimines derived from isatins by using chiral 1,3‐bis(imidazolin‐2‐yl)benzene (Phebim)–PdII complexes afforded products with good enantioselectivity (see scheme). The reaction was applied to a wide variety of ketimines. The obtained product can be converted to homoallylic amines and a spirocyclic amine without the loss of enantiopurity.