Mia N. Burhardt, Andreas Ahlburg, and Troels Skrydstrup*
dx.doi.org/10.1021/jo5009965
J. Org. Chem., 2014 Articles ASAP read more →

A catalytic protocol for synthesis of thioesters from aryl, vinyl, and benzyl bromides as well as benzyl chlorides was developed using only stoichiometric amounts of carbon monoxide, produced from a solid CO precursor inside a two-chamber system. As a catalytic system, the combination of bis(benzonitrile) palladium(II) chloride and Xantphos furnished the highest yields of the desired compounds, along with the weak base, NaOAc, in anisole at 120 °C. The choice of catalytic system as well as solvent turned out to be important in order to ensure a high chemoselectivity in the reaction. Both electron-rich and electron-deficient aryl bromides worked well in this reaction. Addition of 1 equiv of sodium iodide to the reaction improved the chemoselectivity with the electron-deficient aryl bromides. The thiol scope included both aryl and alkyl thiols, including 2-mercaptobenzophenones, whereby a thiocarbonylation followed by a subsequent McMurry coupling yielded differently substituted benzothiophenes. It was demonstrated that the methodology could be applied for ¹³C introduction into the thiophene ring.

Palladium-Catalyzed Thiocarbonylation of Aryl, Vinyl, and Benzyl Bromides

Mia N. Burhardt, Andreas Ahlburg, and Troels Skrydstrup^*

Center for Insoluble Protein Structures, Department of Chemistry and Interdisciplinary Nanoscience Center, Aarhus University, Gustav Wieds vej 14, 8000 Aarhus C, Denmark

J. Org. Chem., 2014, 79 (24), pp 11830–11840

DOI: 10.1021/jo5009965

Publication Date (Web): June 12, 2014

*E-mail: ts@chem.au.dk.

This article is part of the Mechanisms in Metal-Based Organic Chemistry special issue.

http://pubs.acs.org/doi/abs/10.1021/jo5009965

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