Polystyrene-Supported (2<i>S</i>)-(−)-3-<i>exo</i>-Piperazinoisoborneol: An Efficient Catalyst for the Batch and Continuous Flow Production of Enantiopure Alcohols
作者:Laura Osorio-Planes、Carles Rodríguez-Escrich、Miquel A. Pericàs
DOI:10.1021/ol300415f
日期:2012.4.6
(PS-PIB) of 3-exo-morpholinoisoborneol (MIB), designed for increased chemical stability, has been synthesized and used as a ligand in the asymmetric alkylation of aldehydes with Et2Zn. The supportedligand turned out to be highly active and enantioselective for a broad scope of substrates (92–99% ee), allowing repeated recycling. A single-pass, continuousflow process implemented with PS-PIB shows only
Highly Enantio- and Diastereoselective One-Pot Synthesis of Acyclic Epoxy Alcohols with Three Contiguous Stereocenters
作者:Alice E. Lurain、Aaron Maestri、Ann Rowley Kelly、Patrick J. Carroll、Patrick J. Walsh
DOI:10.1021/ja046750g
日期:2004.10.1
Two highly enantio- and diastereoselective one-pot procedures for the synthesis of epoxy alcohols with up to three contiguous stereocenters are reported. Route one involves asymmetricaddition of an alkylzinc reagent to an enal followed by diastereoselective epoxidation. Route two entails asymmetric vinylation of an aldehyde with divinylzinc reagents and subsequent diastereoselective epoxidation. The
CuH-Catalyzed Enantioselective 1,2-Reductions of α,β-Unsaturated Ketones
作者:Ralph Moser、Žarko V. Bošković、Christopher S. Crowe、Bruce H. Lipshutz
DOI:10.1021/ja102689e
日期:2010.6.16
The first study on a general technology for arriving at valued nonracemic allylic alcohols using asymmetricligand-acceleratedcatalysis by copper hydride is described.
Tail-Tied Ligands: An Immobilized Analogue of (R)-2-Piperidino-1,1,2-triphenylethanol with Intact High Catalytic Activity and Enantioselectivity
作者:Miquel A. Pericàs、David Castellnou、Israel Rodríguez、Antoni Riera、Lluís Solà
DOI:10.1002/adsc.200303125
日期:2003.12
A functional analogue of (R)-2-piperidino-1,1,2-triphenylethanol was synthesized and anchored to different polymeric supports by a position remote from the active region. This strategy, leading to what we call a tail-tiedligand, allows for the achievement of the optimal transition state geometry in the catalytic process. The catalyticactivity of the resulting heterogenized ligands was investigated
Novel C2-symmetric chiral O,N,N,O-tetradentate 2,2-bipyridyldiolpropane ligands: synthesis and application in asymmetric diethylzinc addition to aldehydes
作者:Yi-Shan Shih、Ramalingam Boobalan、Chinpiao Chen、Gene-Hsian Lee
DOI:10.1016/j.tetasy.2013.12.020
日期:2014.2
C2-symmetric chiralO,N,N,O-tetradentate 2,2-bipyridyldiolpropane ligands is described. The Mukaiyama–Michael reaction was applied as an important reaction for the synthesis of 2,2-bipyridylpropane 9. Among the ligands synthesized, ligand 11 exhibits excellent chiral induction (up to 97% ee) in diethylzincaddition to various aldehydes. The use of additional Lewis acid such as Ti(OiPr)4 in diethylzinc addition
描述了C 2对称的手性O,N,N,O-四齿2,2-联吡啶二醇二醇丙烷配体的合成。Mukaiyama–Michael反应被用作合成2,2-联吡啶丙烷9的重要反应。在合成的配体中,配体11在二乙基锌和各种醛类化合物中均表现出出色的手性诱导(至多97%ee)。对于本催化体系,不需要在二乙基锌加成反应中使用额外的路易斯酸,例如Ti(O i Pr)4。