Chiral Dirhodium Tetraphosphate-Catalyzed Enantioselective Si–H Bond Insertion of α-Aryldiazoacetates

Abstract

A highly enantioselective Si−H bond insertion reaction of α-aryldiazoacetates catalyzed by chiral spiro dirhodium tetraphosphate was developed. Various chiral α-silyl esters were prepared with high yield (up to 92%) and excellent enantioselectivity (up to >99% ee) through this protocol. It is noteworthy that the 2-substituted aryl diazoacetates, which are challenging substrates for other chiral dirhodium catalysts, also exhibited good results in this reaction. This work represents one of the few successful applications of chiral dirhodium phosphates in asymmetric catalysis.

Chiral organophosphates as ligands in asymmetric metal catalysis

“…In the chiral environment of the catalyst, this leads to a 2.2 kcal preference for the experimentally observed product isomer. This pioneering work on Si-H activation by diaryldiazomethanes was extended to the use of arylalkynyldiazomethanes 50 and diazoacetates 51 (not shown in detail).…”

“…This pioneering work on Si–H activation by diaryldiazomethanes was extended to the use of arylalkynyldiazomethanes 50 and diazoacetates 51 (not shown in detail).…”