Chiral selenium π-acid catalysis has for a long time been lagging behind other areas of asymmetriccatalysis due to a lack of highly enantioselective catalysts. In this regard, we recently developed the firstchiral selenium π-acid catalyst which performs the oxidative cyclization of β,γ-unsaturated carboxylic acids with high enantioselectivities. We report herein our improved synthesis of this chiral
A Chiral Electrophilic Selenium Catalyst for Highly Enantioselective Oxidative Cyclization
作者:Yu Kawamata、Takuya Hashimoto、Keiji Maruoka
DOI:10.1021/jacs.6b01462
日期:2016.4.27
Chiral electrophilic selenium catalysts have been applied to catalytic asymmetric transformations of alkenes over the past two decades. However, highlyenantioselective reactions with a broad substrate scope have not yet been developed. We report the first successful example of this reaction employing a catalyst based on a rigid indanol scaffold, which can be easily synthesized from a commercially
Switchable Site-Selective Catalytic Carboxylation of Allylic Alcohols with CO<sub>2</sub>
作者:Manuel van Gemmeren、Marino Börjesson、Andreu Tortajada、Shang-Zheng Sun、Keisho Okura、Ruben Martin
DOI:10.1002/anie.201702857
日期:2017.6.1
allylic alcohols has been developed in which CO2 is used with dual roles, both facilitating C-OH cleavage and as a C1 source. This protocol is characterized by its mild reaction conditions, absence of stoichiometric amounts of organometallicreagents, broad scope, and exquisite regiodivergency which can be modulated by the type of ligand employed.
A direct, palladium-catalyzed, carbonylative transformation of allylicalcohols for the synthesis of β,γ-unsaturated carboxylic acids has been developed. With formic acid as the CO source, various allylicalcohols were conveniently transformed into the corresponding β,γ-unsaturated carboxylic acids with excellent linear and (E)-selectivity. The reaction was performed under mild conditions; toxic CO