Boron-Catalyzed, Diastereo- and Enantioselective Allylation of Ketones with Allenes
Kieran Nicholson, Yuxuan Peng, Natalia Llopis, Dominic R. Willcox, Gary S. Nichol, Thomas Langer, Alejandro Baeza, Stephen P. Thomas
Abstract
The diastereo- and enantioselective allylation of ketones remains a synthetic challenge, with transition metal catalysis offering the most applied methods. Here, a boron-catalyzed allylation of ketones with allenes is presented. Excellent yield, regioselectivity, and diastereoselectivity were found across functionalized substrates. The reaction was further developed to accommodate an enantioenriched boron catalyst and thus gave asymmetric ketone allylation in good yield, diastereoselectivity, and enantioselectivity. Mechanistic studies supported a hydroboration-allylation-transborylation pathway.
Topics & Concepts
Enantioselective synthesisHydroborationRegioselectivityCatalysisChemistryKetoneYield (engineering)BoronOrganic chemistryCombinatorial chemistryMaterials scienceMetallurgyOrganoboron and organosilicon chemistryChemical Synthesis and AnalysisCatalytic C–H Functionalization Methods