Journal of the American Chemical Society, Vol.141, No.27, 10599-10604, 2019
Chiral Bidentate Boryl Ligand Enabled Iridium-Catalyzed Enantioselective C(sp(3))-H Borylation of Cyclopropanes
We herein report an Ir-catalyzed enantioselective C(sp(3))-H borylation of cyclopropanecarboxamides using a chiral bidentate boryl ligand for the first time. A variety of substrates with alpha-quaternary carbon centers could be compatible in this reaction to provide beta-borylated products with good to excellent enantioselectivities. We have also demonstrated that the borylated products can be used as versatile precursors engaging in stereospecific transformations of C-B bonds, including the synthesis of a bioactive compound Levomilnacipran.