Site‐ and Stereoselective C(<i>sp</i><sup>3</sup>)−H Borylation of Strained (Hetero)Cycloalkanols Enabled by Iridium Catalysis
Qian Gao, Senmiao Xu
Abstract
Abstract Transition metal‐catalyzed site‐ and stereoselective C−H activation of strained (hetero)cycloalkanes remains a formidable challenge. We herein report a carbamate‐directed iridium‐catalyzed asymmetric β−C( sp 3 )−H borylation of cyclopropanol derivatives. A variety of densely functionalized cyclopropanols were obtained in good enantioselectivities via desymmetrization and kinetic resolution. In addition, site‐selective C( sp 3 )−H borylation of methine groups furnished α‐borylated (hetero)cycloalkanols in moderate to good yields. The synthetic utility of the method was further shown in a gram‐scale synthesis and diverse downstream transformations of borylated products.
Topics & Concepts
BorylationDesymmetrizationChemistryIridiumStereoselectivityCatalysisKinetic resolutionCombinatorial chemistryOrganic chemistryMedicinal chemistryEnantioselective synthesisStereochemistryArylAlkylCatalytic C–H Functionalization MethodsCatalytic Cross-Coupling ReactionsOrganoboron and organosilicon chemistry