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Detection of Palladium(I) in Aerobic Oxidation Catalysis.

ABSTRACT: Palladium(II)-catalyzed oxidation reactions exhibit broad utility in organic synthesis; however, they often feature high catalyst loading and low turnover numbers relative to non-oxidative cross-coupling reactions. Insights into the fate of the Pd catalyst during turnover could help to address this limitation. Herein, we report the identification and characterization of a dimeric PdI species in two prototypical Pd-catalyzed aerobic oxidation reactions: allylic C-H acetoxylation of terminal alkenes and intramolecular aza-Wacker cyclization. Both reactions employ 4,5-diazafluoren-9-one (DAF) as an ancillary ligand. The dimeric PdI complex, [PdI (?-DAF)(OAc)]2 , which features two bridging DAF ligands and two terminal acetate ligands, has been characterized by several spectroscopic methods, as well as single-crystal X-ray crystallography. The origin of this PdI complex and its implications for catalytic reactivity are discussed.

SUBMITTER: Jaworski JN

PROVIDER: S-EPMC5499979 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Detection of Palladium(I) in Aerobic Oxidation Catalysis.

Jaworski Jonathan N JN McCann Scott D SD Guzei Ilia A IA Stahl Shannon S SS

Angewandte Chemie (International ed. in English) 20170220 13

Palladium(II)-catalyzed oxidation reactions exhibit broad utility in organic synthesis; however, they often feature high catalyst loading and low turnover numbers relative to non-oxidative cross-coupling reactions. Insights into the fate of the Pd catalyst during turnover could help to address this limitation. Herein, we report the identification and characterization of a dimeric Pd<sup>I</sup> species in two prototypical Pd-catalyzed aerobic oxidation reactions: allylic C-H acetoxylation of ter ...[more]

PMID: 28217896

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