Scope, Limitations and Mechanistic Analysis of the HyperBTM‐Catalyzed Acylative Kinetic Resolution of Tertiary Heterocyclic Alcohols**
作者:Samuel M. Smith、Mark D. Greenhalgh、Taisiia Feoktistova、Daniel M. Walden、James E. Taylor、David B. Cordes、Alexandra M. Z. Slawin、Paul Ha‐Yeon Cheong、Andrew D. Smith
DOI:10.1002/ejoc.202101111
日期:2022.1.11
isothiourea HyperBTM catalyzes the acylative kinetic resolution of a wide range of tertiary heterocyclic alcohols under mild conditions with high selectivity. The synthetic utility of the methodology has been demonstrated with the preparation of two bioactive targets. Kinetic analysis reveals a fractional reaction order with respect to the alcohol concentration.
A Facile Pathway to Enantiomerically Enriched 3-Hydroxy-2-Oxindoles: Asymmetric Intramolecular Arylation of α-Keto Amides Catalyzed by a Palladium-DifluorPhos Complex
作者:Liang Yin、Motomu Kanai、Masakatsu Shibasaki
DOI:10.1002/anie.201102158
日期:2011.8.8
Less metal wastes: The first catalytic, enantioselective intramolecular aryl‐transfer reaction of aryl triflates to ketones has been developed (see scheme; R1=R2=aromatic and aliphatic). This method features overall practicality, including substrate stability and accessibility (protecting‐group free) plus no need for the use of stoichiometric amounts of metals.
减少金属废料:已开发出芳基三氟甲磺酸酯向酮的第一个催化,对映选择性分子内芳基转移反应(参见方案; R 1 = R 2 =芳族和脂族)。该方法具有整体实用性,包括基材稳定性和可及性(无保护基团),而且无需使用化学计量的金属。
Rh(I)-catalyzed asymmetric addition of arylboronic acids to NH isatins
作者:Jiangyang Gui、Guihua Chen、Peng Cao、Jian Liao
DOI:10.1016/j.tetasy.2012.04.013
日期:2012.4
The transition metal-catalyzed asymmetric variant of the title reaction is normally limited to N-protected isatins. However, Rh(I)/chiral sulfoxide phosphine complexes were found to catalyze the enantioselective addition of arylboronicacids to NH isatins under mild conditions. A variety of chiral 3-aryl-3-hydroxyl-2-oxindoles were obtained with high yields and with good to excellent enantioselectivities
Arylboronic Acid-Catalyzed Racemization of Secondary and Tertiary Alcohols
作者:Gregory R. Boyce、Stefania F. Musolino、Jianing Yang、Andrew D. Smith、James E. Taylor
DOI:10.1021/acs.joc.2c01602
日期:2022.10.7
The use of 2-carboxyphenylboronic acid (5 mol %) and oxalic acid (10 mol %) with 2-butanone as a solvent for the racemization of a range of enantiomerically pure secondary and tertiaryalcohols is demonstrated. The process is postulated to proceed via reversible Brønsted acid-catalyzed C–O bond cleavage through an achiral carbocation intermediate.