Construction of Chiral Quaternary Carbon through Morita-Baylis-Hillman Reaction: An Enantioselective Approach to 3-Substituted 3-Hydroxyoxindole Derivatives
作者:Xiao-Yang Guan、Yin Wei、Min Shi
DOI:10.1002/chem.201002240
日期:2010.12.10
A new enantioselectiveapproach to obtain a tetrasubstituted chiral center at the C3 position of oxindoles via a catalytic asymmetric Morita–Baylis–Hillmanreaction has been demonstrated. This reaction provides 3‐substituted 3‐hydroxy‐2‐oxindoles in good to excellent yields and ee values, which could be facilely transformed to pharmaceutically more interesting compounds.
Organocatalytic Enantioselective Mukaiyama–Mannich Reaction of Isatin‐Derived Ketimines for the Synthesis of Oxindolyl‐
<i>β</i>
<sup>3, 3</sup>
‐Amino Acid Esters
作者:Saumen Hajra、Sujay Laskar、Bibekananda Jana
DOI:10.1002/chem.201903512
日期:2019.11.18
Mukaiyama-Mannich reactions of ester enolate equivalents with aldimines have been elegantly used for the asymmetric synthesis of β-amino acids; nevertheless, the corresponding asymmetric reaction employing ketimines are unexplored. Herein, the first organocatalytic enantioselective Mukaiyama-Mannich reaction employing isatin-derived ketimines with unsubstituted silyl ketene acetals is disclosed towards
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.