Synthesis 2016; 48(22): 3890-3906
DOI: 10.1055/s-0035-1562793
short review
© Georg Thieme Verlag Stuttgart · New York

The Diamino Analogues of Privileged Corey–Bakshi–Shibata and Jørgensen–Hayashi Catalysts: A Comparison of Their Performance

Jorge Vargas-Caporali*
a   Departamento de Química, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Avenida IPN No. 2508, 07360 Ciudad de México, México   Email: jvargas@relaq.mx   Email: juaristi@relaq.mx
,
Eusebio Juaristi*
a   Departamento de Química, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Avenida IPN No. 2508, 07360 Ciudad de México, México   Email: jvargas@relaq.mx   Email: juaristi@relaq.mx
b   El Colegio Nacional, Luis González Obregón No. 23, Centro Histórico, 06020 Ciudad de México, México
› Author Affiliations
Further Information

Publication History

Received: 28 June 2016

Accepted: 29 June 2016

Publication Date:
01 September 2016 (online)


Abstract

α,α-Diarylprolinol derivatives are well-established families of organocatalysts that are widely used to promote diverse asymmetric reactions. The enantioinduction generated from these ligands is mainly due to the gem-diphenyl carbinol fragment. For this reason, the synthesis of diaza analogues seemed an evident and attractive issue to address in the development of alternative chiral ligands. Although the O→N substitution and subsequent derivatization at first glance looked simple, it was necessary to deal with various unexpected synthetic difficulties. It was established that suitable modifications of the side chain in the diaza analogues afford reaction yields and stereoselectivities that are comparable to those exhibited by the amino alcohol analogues. Nevertheless, various potential applications still remain undeveloped.

1 Introduction

2 Oxazaborolidines and Diazaborolidines in Borane-Mediated Reduction of Prochiral Ketones

3 Organocatalyzed Asymmetric Epoxidations

4 Assessing the Organocatalytic Capability of the α,α-Diphenylprolinol Diaza-Analogues through Benchmark Mannich and Michael Reactions

 
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