Synthesis 2016; 48(17): 2789-2794
DOI: 10.1055/s-0035-1561669
special topic
© Georg Thieme Verlag Stuttgart · New York

Nickel-Catalyzed Enantioselective Synthesis of Cyclobutenes via [2+2] Cycloaddition of α,β-Unsaturated Carbonyls with 1,3-Enynes

Ravindra Kumar
a   Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
,
Eri Tamai
a   Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
,
Akira Ohnishi
a   Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
,
Akira Nishimura
a   Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
,
Yoichi Hoshimoto
a   Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
b   Frontier Research Base for Global Young Researchers, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
,
Masato Ohashi
a   Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
,
Sensuke Ogoshi*
a   Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
› Author Affiliations
Further Information

Publication History

Received: 10 March 2016

Accepted after revision: 09 May 2016

Publication Date:
23 June 2016 (online)


Abstract

A Ni(0)/chiral N-heterocyclic carbene (NHC) catalyzed enantioselective and intermolecular [2+2] cycloaddition of α,β-unsaturated carbonyl compounds with conjugated enynes was investigated to produce enantioenriched cyclobutenes (up to 89% ee). The present report reveals the first example of a nickel-catalyzed enantioselective [2+2]-cycloaddition reaction. A newly synthesized imidazolinium salt, L*12·HBF4, was the most effective NHC precursor for the present catalytic reactions.

Supporting Information