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

Haohua Huo; Xiaoqiang Huang; Xiaodong Shen; Klaus Harms; Eric Meggers

doi:10.1055/s-0035-1561284

Synlett, Table of Contents

Synlett 2016; 27(05): 749-753
DOI: 10.1055/s-0035-1561284

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

Haohua Huo

^aFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany

,

Xiaoqiang Huang

^aFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany

,

Xiaodong Shen

^aFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany

,

Klaus Harms

^aFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany

,

Eric Meggers*

^aFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany

^bCollege of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. of China Email: meggers@chemie.uni-marburg.de

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Abstract

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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.

Key words

photoredox catalysis - asymmetric catalysis - visible light - perfluoroalkylation - radical reaction - electron catalysis

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References

References and Notes

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