(R, R)-(+)-2-[Benzyl-(2-hydroxy-2-phenylethyl)amino]-1-phenylethanol 1 is used as a chiral ligand in the synthesis of an optically active lanthanum-sodium amino diol complex LS-1. This heterobimetallic catalyst is quite effective as an asymmetric catalyst for various Michael addition reactions, 1H NMR study indicates the co-ordination of enone to the central lanthanum atom in LS-1. The reaction conditions were optimized and the adducts were obtained in high yield with moderate to high enantiomeric excess under extremely mild conditions. © 2002 Elsevier Science Ltd. All rights reserved.

Govindarajan Sundararajan

2 [BENZYL(2 HYDROXY 2 PHENYLETHYL)AMINO] 1 PHENYLETHANOL

Lanthanum

ligand

PHENETHYL ALCOHOL

Sodium

unclassified drug

article

asymmetric catalysis

asymmetric synthesis

atom

catalyst

chemical reaction

chirality

enantiomer

Optical rotation

priority journal

proton nuclear magnetic resonance

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Asymmetric Michael addition reactions using a chiral La–Na aminodiolate catalyst

Tetrahedron Asymmetry

For the first time, asymmetric 1,4-addition of various malonates to enones has been carried out using tetrabutylammoniumtetrahydroborate (TBATB) in the presence of a chiral ligand. The Michael adducts were formed in reasonably good yields (61-67%) with moderate ee's at 0°C. 11B NMR spectroscopic studies explain this unexpected reactivity through the predominant formation of an aminodiol modified borate complex in the presence of a hydride acceptor. © 2005 Elsevier Ltd. All rights reserved.

Tetrahedron

Investigation of the active species in a Michael addition promoted by chirally modified tetrahydroborate

(matrix presented) R1, R2 = (-OCH2CH2-), (-OCH2CH2CH2-), (-CH=CH-CH2-), (-OCH2CH3, H) (R,R)-3-Aza-3-benzyl-1,5-dihydroxy-1,5-diphenylpentane (1) ligated Ti(IV) complex (1-TiCl2) is used as a chiral Lewis acid catalyst for promoting asymmetric IED Diels-Alder reaction between electron-rich dienophiles and electron-poor dienes. Here we introduce a facile route for the synthesis of asymmetric tetrahydroquinoline derivatives using the above-mentioned chiral catalyst reagent in the presence of 4 Å molecular sieves. The reactions proceed with moderate yields and at times high enantioselectivty.

Organic Letters

First Asymmetric Synthesis of Quinoline Derivatives by Inverse Electron Demand (IED) Diels-Alder Reaction Using Chiral Ti(IV) Complex

Synfacts

Synthesis of Benzazoles Catalyzed by Sodium tert-Butoxide

Tetrahedron: Asymmetry

Chemoenzymatic synthesis of enantiopure 1,1′-disubstituted ferrocenyl aminoalcohols

Angewandte Chemie International Edition

The First Catalytic Asymmetric Nitro-Mannich-Type Reaction Promoted by a New Heterobimetallic Complex

Enantioselective Ring Opening of Epoxides with 4-Methoxyphenol Catalyzed by Gallium Heterobimetallic Complexes: An Efficient Method for the Synthesis of Optically Active 1,2-Diol Monoethers

Asymmetric Michael addition reactions using a chiral La-Na aminodiolate catalyst

Journal	Tetrahedron Asymmetry
ISSN	09574166
Open Access	No