Carbonylative Coupling of Alkyl Zinc Reagents with Benzyl Bromides Catalyzed by a Nickel/NN2 Pincer Ligand Complex. Issue 3 (18th December 2017)

• Record Type: Journal Article
• Authors: Andersen, Thomas L.; Donslund, Aske S.; Neumann, Karoline T.; Skrydstrup, Troels
• Is Part Of: Angewandte Chemie international edition. Volume 57:Issue 3(2018)
• Page Start: 800
• Page End: 804
• Publication Date: 2017-12-18
• Subjects: carbonylation -- ketones -- nickel -- N ligands -- reaction mechanisms; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201710089
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: An efficient catalytic protocol for the three‐component assembly of benzyl bromides, carbon monoxide, and alkyl zinc reagents to give benzyl alkyl ketones is described, and represents the first nickel‐catalyzed carbonylative coupling of two sp 3 ‐carbon fragments. The method, which relies on the application of nickel complexed with an NN2 ‐type pincer ligand and a controlled release of CO gas from a solid precursor, works well with a range of benzylic bromides. Mechanistic studies suggest the intermediacy of carbon‐centered radicals. Abstract : Hold tight : Nickel(II)/NN2 ‐type pincer ligand complexes are employed as catalysts in the title reaction. It involves controlled release of CO(g) from a solid precursor, and thus circumvents nickel catalyst deactivation upon CO saturation. The first nickel‐catalyzed carbonylative couplings of two sp 3 ‐hybridized carbon centers are reported. The reaction conditions are mild and near‐stoichiometric amounts of CO are used.