Issue 1, 2017

Effective asymmetric vinylogous Mannich reaction of isatin imines with α,α-dicyanoolefins in the presence of a simple chiral amide phosphonium bifunctional phase transfer catalyst

Abstract

An asymmetric vinylogous Mannich reaction between α,α-dicyanoolefins and N-Boc isatin imines has been developed by employing 1 mol% bifunctional amide phosphonium salt as a phase transfer catalyst and K2CO3 as a base. When α,α-dicyanoolefins derived from aryl methyl ketones were used as substrates, the normal Mannich adducts of 3,3-disubstituted aminooxindoles were obtained in good to excellent yields with high ee values, while α,α-dicyanoolefins derived from tetralone, propiophenone and methyl tert-butyl ketone led to cyclized products through a cascade sequence of Mannich reaction and intramolecular cyclization. The α,α-dicyanoolefin moiety in the Mannich adduct may be used as an aryl methyl ketone surrogate and the corresponding 3,3-disubstituted aminooxindole ketones may be effectively obtained after removal of the malonic nitrile by KMnO4 oxidation on a gram scale.

Graphical abstract: Effective asymmetric vinylogous Mannich reaction of isatin imines with α,α-dicyanoolefins in the presence of a simple chiral amide phosphonium bifunctional phase transfer catalyst

Supplementary files

Article information

Article type
Research Article
Submitted
15 Sep 2016
Accepted
19 Oct 2016
First published
20 Oct 2016

Org. Chem. Front., 2017,4, 101-114

Effective asymmetric vinylogous Mannich reaction of isatin imines with α,α-dicyanoolefins in the presence of a simple chiral amide phosphonium bifunctional phase transfer catalyst

C. Cheng, X. Lu, L. Ge, J. Chen, W. Cao, X. Wu and G. Zhao, Org. Chem. Front., 2017, 4, 101 DOI: 10.1039/C6QO00546B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements