Enantioselective Synthesis of Axially Chiral Biaryls via Copper-Catalyzed Thiolation of Cyclic Diaryliodonium Salts.

Here, we report a chiral copper(II)-bisoxazoline-catalyzed enantioselective ring opening of cyclic diaryliodonium salts with heteroaryl thiols. The readily available 2-mercaptobenzoxazole and 2-mercaptobenzothiazole derivatives reacted efficiently with cyclic diaryliodonium salts and afforded various axially chiral biaryls bearing iodine and sulfur functional groups in excellent yields and enantioselectivities. The products were further transformed into diverse enantiopure alkyl biaryl sulfides, which can be employed as chiral ligands.