title: A highly active phosphine-borane organocatalyst for the reduction of CO2 to methanol using hydroboranes.
abstract: In this work, we report that organocatalyst 1-Bcat-2-PPh2-C6H4 ((1); cat = catechol) acts as an ambiphilic metal-free system for the reduction of carbon dioxide in presence of hydroboranes (HBR2 = HBcat (catecholborane), HBpin (pinacolborane), 9-BBN (9-borabicyclo[3.3.1]nonane), BH3·SMe2 and BH3·THF) to generate CH3OBR2 or (CH3OBO)3, products that can be readily hydrolyzed to methanol. The yields can be as high as 99% with exclusive formation of CH3OBR2 or (CH3OBO)3 with TON (turnover numbers) and TOF (turnover frequencies) reaching >2950 and 853 h(-1), respectively. Furthermore, the catalyst exhibits "living" behavior: once the first loading is consumed, it resumes its activity on adding another loading of reagents.
authors.affiliation: Département de Chimie, Centre de Catalyse et de Chimie Verte (C3V), Université Laval, Québec G1V 0A6, Canada.
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Courtemanche
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Légaré
authors.forename: Laurent
authors.initials: L
authors.lastname: Maron
authors.forename: Frédéric-Georges
authors.initials: FG
authors.lastname: Fontaine
mesh_terms: D001880:Boranes / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D000432:Methanol / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010720:Phosphines / Q000737:chemistry*
chemical_list: D001880:Boranes; D010720:Phosphines; D002245:Carbon Dioxide; C044646:phosphine; D000432:Methanol