Nickel-Catalyzed Reductive Cross-Coupling of Xanthate Esters With Aryl and Alkenyl Iodides
Felix Vöhringer1, Kathrin Zwettler1, Dmitry I Sharapa2
1Institute of Organic Chemistry, Faculty of Science, Eberhard Karls Universität Tübingen, Tübingen, Germany.
Abstract:
We report a nickel-catalyzed reductive cross-coupling of xanthate esters and aryl and alkenyl iodides. Utilizing xanthate esters with an S-allyl substituent leads to higher yields compared to the more commonly used S-Me xanthate esters. The reaction is tolerant toward a wide array of functional groups and allows for the conversion of xanthate esters derived from pharmaceuticals to diarylmethanes. Electronic properties of the reaction partners have a strong influence on the reaction. Mechanistic investigations revealed that the benzylic radical is generated from the xanthate ester, presumably by single electron transfer by Ni(I).
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