Synlett 2016; 27(05): 749-753
DOI: 10.1055/s-0035-1561284
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© Georg Thieme Verlag Stuttgart · New York

Visible-Light-Activated Enantioselective Perfluoroalkylation with a Chiral Iridium Photoredox Catalyst

Haohua Huo
a  Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
,
Xiaoqiang Huang
a  Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
,
Xiaodong Shen
a  Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
,
Klaus Harms
a  Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
,
Eric Meggers*
a  Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
b  College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. of China   Email: meggers@chemie.uni-marburg.de
› Author Affiliations
Further Information

Publication History

Received: 31 October 2015

Accepted: 18 November 2015

Publication Date:
23 December 2015 (online)

Abstract

A visible-light-activated enantioselective radical perfluoroalkylation of 2-acyl imidazoles with perfluoroalkyl iodides (CF3I, C3F7I, C4F9I, C6F13I, C8F17I and C10F21I) and perfluorobenzyl iodide at the α-position of the carbonyl group is reported. Enantioselectivities with up to >99.5% ee are achieved. The process uses a dual-function chiral Lewis acid/photoredox catalyst at loadings of 2–4 mol% and constitutes a redox-neutral, electron-catalyzed reaction that proceeds via intermediate perfluoroalkyl radicals.

Supporting Information

 
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