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DOI: 10.1055/s-0041-1737816
Generation of Thiyl Radicals from Air-Stable, Odorless Thiophenol Surrogates: Application to Visible-Light-Promoted C–S Cross-Coupling
This work was supported by the Engineering and Physical Sciences Research Council (EPSRC) Centre for Doctoral Training in Sustainable Chemistry (EP/S022236/1) through a Ph.D. studentship to C.S., and a UKRI Future Leaders Fellowship to L.T.B. (MR/V022067/1).
Abstract
The synthetic versatility of thiophenols is offset by their air-sensitivity and foul odor. It is demonstrated that S-aryl isothiouronium salts can be used as precursors to thiyl radicals, extending the practical benefits of these air-stable, odorless salts from ionic to single electron manifolds. The isothiouronium salts are accessed via Ni-catalyzed cross-coupling of (hetero)aryl iodides and thiourea and are isolated as free-flowing solids following anion exchange. Judicious choice of a redox-innocent counteranion enables use of these convenient thiophenol surrogates in radical processes, as is exemplified by the synthesis of non-symmetrical diaryl thioethers via light-promoted S-arylation.
Key words
thiophenols - nickel catalysis - C–S cross-coupling - photochemistry - electron donor–acceptor complexes - thiyl radicals - diaryl sulfidesSupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0041-1737816.
- Supporting Information
Publication History
Received: 13 October 2021
Accepted after revision: 10 January 2022
Article published online:
10 February 2022
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