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Site-Selective C-S Bond Formation at C-Br over C-OTf and C-Cl Enabled by an Air-Stable, Easily Recoverable, and Recyclable Palladium(I) Catalyst.

ABSTRACT: This report widens the repertoire of emerging Pd^I catalysis to carbon-heteroatom, that is, C-S bond formation. While Pd⁰ -catalyzed protocols may suffer from the formation of poisonous sulfide-bound off-cycle intermediates and lack of selectivity, the mechanistically diverse Pd^I catalysis concept circumvents these challenges and allows for C-S bond formation (S-aryl and S-alkyl) of a wide range of aryl halides. Site-selective thiolations of C-Br sites in the presence of C-Cl and C-OTf were achieved in a general and a priori predictable fashion. Computational, spectroscopic, X-ray, and reactivity data support dinuclear Pd^I catalysis to be operative. Contrary to air-sensitive Pd⁰ , the active Pd^I species was easily recovered in the open atmosphere and subjected to multiple rounds of recycling.

SUBMITTER: Scattolin T

PROVIDER: S-EPMC6468269 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Site-Selective C-S Bond Formation at C-Br over C-OTf and C-Cl Enabled by an Air-Stable, Easily Recoverable, and Recyclable Palladium(I) Catalyst.

Scattolin Thomas T Senol Erdem E Yin Guoyin G Guo Qianqian Q Schoenebeck Franziska F

Angewandte Chemie (International ed. in English) 20180820 38

This report widens the repertoire of emerging PdI catalysis to carbon-heteroatom, that is, C-S bond formation. While Pd0 -catalyzed protocols may suffer from the formation of poisonous sulfide-bound off-cycle intermediates and lack of selectivity, the mechanistically diverse PdI catalysis concept circumvents these challenges and allows for C-S bond formation (S-aryl and S-alkyl) of a wide range of aryl halides. Site-selective thiolations of C-Br sites in the pres ...[more]

PMID: 30014554

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