Evaluation of Cobalt Complexes Bearing Tridentate Pincer Ligands for Catalytic C–H Borylation

Autor:	Grant W. Margulieux, Brian A. Schaefer, Brooke L. Small, Paul J. Chirik
Rok vydání:	2015
Předmět:	Organic Chemistry chemistry.chemical_element Photochemistry Medicinal chemistry Borylation Catalysis Pincer movement Inorganic Chemistry chemistry.chemical_compound chemistry Pyridine Chelation Physical and Theoretical Chemistry Benzene Cobalt Group 2 organometallic chemistry
Zdroj:	Organometallics. 34:1307-1320
ISSN:	1520-6041 0276-7333
Popis:	Cobalt(II) dichloride complexes supported by a variety of neutral, tridentate pincer ligands have been prepared and, following in situ activation with NaBEt3H, evaluated for the catalytic borylation of 2-methylfuran, 2,6-lutidine, and benzene using both HBPin and B2Pin2 (Pin = pinacolate) as boron sources. Preparation of well-defined organometallic compounds in combination with stoichiometric experiments with HBPin and B2Pin2 provided insight into the nature and kinetic stability of the catalytically relevant species. In cases where sufficiently electron donating pincers are present, such as with bis(phosphino)pyridine chelates, Co(III) resting states are preferred and catalytic C–H borylation is efficient. Introduction of a redox-active subunit into the pincer reduces its donating ability and, as a consequence, the accessibility of a Co(III) resting state. In these cases, unusual mixed-valent μ-hydride cobalt complexes have been crystallographically and spectroscopically characterized. These studies have...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::87dcd70a1d789e794ec5ac7130573cda https://doi.org/10.1021/acs.organomet.5b00044 Zobrazit plný text záznamu