Synthesis 2017; 49(02): 310-318
DOI: 10.1055/s-0036-1589401
paper
© Georg Thieme Verlag Stuttgart · New York

Asymmetric Hydrogenation of Cyclic Imines and Enamines: Access to 1,5-Benzodiazepine Pharmacophores

Ruediger Borrmann
Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany   Email: magnus.rueping@rwth-aachen.de
,
Rene M. Koenigs
Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany   Email: magnus.rueping@rwth-aachen.de
,
Jochen Zoller
Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany   Email: magnus.rueping@rwth-aachen.de
,
Magnus Rueping*
Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany   Email: magnus.rueping@rwth-aachen.de
› Author Affiliations
Further Information

Publication History

Received: 18 September 2016

Accepted: 30 September 2016

Publication Date:
13 October 2016 (online)


Dedicated to Prof. Dieter Enders on the occasion of his 70th birthday

Abstract

A new strategy towards the pharmacologically relevant class of dihydro-1,5-benzodiazepines was developed by applying a rhodium-catalyzed asymmetric hydrogenation. The approach represents an efficient protocol providing access to the optically active products in excellent yields (up to 99%) and with high enantioselectivities (up to 92% ee). The versatility of the methodology was demonstrated by a broad substrate scope including alkyl, aryl, and heteroaryl substituents as well as halides. Furthermore, investigations regarding the reaction mechanism were performed and unraveled a preferred reaction of the tautomeric enamine in the rhodium-catalyzed asymmetric hydrogenation.

Supporting Information