title: Synthesis of air- and moisture-stable, storable chiral oxorhenium complexes and their application as catalysts for the enantioselective imine reduction.
abstract: Air-/moisture-stable, crystalline, and storable chiral salicyloxazoline based oxorhenium(V) complexes have been synthesized and their catalytic application for the asymmetric reduction of ketimines using hydrosilane as hydride source is disclosed. A broad substrate scope, high yields, and excellent enantioselectivities (up to 99 %) are attained. Furthermore, the syntheses of enantiopure α-amino esters, γ- and δ-lactams, and isoindolinones have also been carried out using this methodology. Finally, the method has been applied to synthetic targets of pharmaceutical relevance, such as R-(+)-salsolidine and R-(+)-crispine A.
authors.affiliation: Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Indore By-pass Road, Bhopal-462066 (India).
authors.forename: Braja Gopal
authors.initials: BG
authors.lastname: Das
authors.affiliation: Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Indore By-pass Road, Bhopal-462066 (India).
authors.forename: Rajender
authors.initials: R
authors.lastname: Nallagonda
authors.affiliation: Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Indore By-pass Road, Bhopal-462066 (India).
authors.forename: Dhananjay
authors.initials: D
authors.lastname: Dey
authors.affiliation: Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Indore By-pass Road, Bhopal-462066 (India). pghorai@iiserb.ac.in.
authors.forename: Prasanta
authors.initials: P
authors.lastname: Ghorai
keywords: asymmetric catalysis; hydrosilylation; ligand effects; natural products; oxorhenium