1,2-Hydroboration of Pyridines by Organomagnesium
Xinli Liu, Bingwen Li, Xiufang Hua, Dongmei Cui
Abstract
Hydroboration of pyridine derivatives at room temperature with earth-abundant and biocompatible magnesium catalysts ligated by phosphinimino amides is developed. Fine turnover frequency (TOF) and distinguished 1,2-regioselectivity have been achieved. The exclusive chemoselective carbonyl hydroboration happens with competitive TOF. A HBpin assisted mechanism is deduced by the reaction rate law, activation parameters, and kinetic isotope effect (KIE) in combination with DFT calculations. To our knowledge, this is the first example of pyridine 1,2-dearomatization by Mg-based catalysts.
Topics & Concepts
HydroborationChemistryPyridineRegioselectivityCatalysisKinetic isotope effectCombinatorial chemistryOrganic chemistryDeuteriumQuantum mechanicsPhysicsOrganoboron and organosilicon chemistryCoordination Chemistry and OrganometallicsAsymmetric Hydrogenation and Catalysis