Access to Enantioenriched Benzylic 1,1-Silylboronate Esters by Palladium-Catalyzed Enantiotopic-Group Selective Suzuki-Miyaura Coupling of (Diborylmethyl)silanes with Aryl Iodide

Junghoon Kim ,  Seung Hwan Cho*

 

  This work describes the palladium-catalyzed enantiotopic-group selective Suzuki–Miyaura cross-coupling of (diborylmethyl)silanes with aryl iodides. The combination of a Pd(TFA)₂ and rev-Josiphos-type ligand bearing a 3,5-bis(trifluoromethyl)phenyl as benzylic phosphine substituent in the presence of NaI as an additive and NaOMe as a base promote the reaction to high efficiency and excellent enantioselectivity. This method provides a convenient approach for synthesizing chiral benzylic 1,1-silylboronate esters from readily accessible reagents. Synthetic applications including stereospecific C–O, C–N, and C–C bond forming reactions of boron group are also demonstrated.   https://pubs.acs.org/doi/10.1021/acscatal.8b03979