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Design of Ru(II)-NHC-Diamine Precatalysts Directed by Ligand Cooperation: Applications and Mechanistic Investigations for Asymmetric Hydrogenation.

ABSTRACT: A modular synthesis of Ru(II)-NHC-diamine complexes from readily available chiral N-heterocyclic carbenes (NHCs) and chiral diamines is disclosed for the first time. The well-defined Ru(II)-NHC-diamine complexes show unique structure and coordination chemistry including an unusual tridentate coordination effect of 1,2-diphenylethylenediamine. The isolated air- and moisture-stable Ru(II)-NHC-diamine complexes act as versatile precatalysts for the asymmetric hydrogenation of isocoumarines, benzothiophene 1,1-dioxides, and ketones. Moreover, on the basis of the identification of reaction intermediates by stoichiometric reactions and NMR experiments, together with the DFT calculations, a possible catalytic cycle was proposed.

SUBMITTER: Li W

PROVIDER: S-EPMC7168601 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Design of Ru(II)-NHC-Diamine Precatalysts Directed by Ligand Cooperation: Applications and Mechanistic Investigations for Asymmetric Hydrogenation.

Li Wei W Wagener Tobias T Hellmann Lars L Daniliuc Constantin G CG Mück-Lichtenfeld Christian C Neugebauer Johannes J Glorius Frank F

Journal of the American Chemical Society 20200401 15

A modular synthesis of Ru(II)-NHC-diamine complexes from readily available chiral N-heterocyclic carbenes (NHCs) and chiral diamines is disclosed for the first time. The well-defined Ru(II)-NHC-diamine complexes show unique structure and coordination chemistry including an unusual tridentate coordination effect of 1,2-diphenylethylenediamine. The isolated air- and moisture-stable Ru(II)-NHC-diamine complexes act as versatile precatalysts for the asymmetric hydrogenation of isocoumarines, benzoth ...[more]

PMID: 32195584

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