Ruthenium-Catalyzed Hydroxylation of Unactivated Tertiary C−H Bonds

摘要

The combination of catalytic RuCl₃ and pyridine with KBrO₃ as the stoichiometric oxidant is shown to efficiently promote the hydroxylation of unactivated tertiary C−H bonds. Substrates possessing different polar functional groups — ester, epoxide, sulfone, oxazolidinone, carbamate, and sulfamate — are found to engage in this reaction to give alcohol products in yields generally exceeding 50%. As judged based on efficiency, ease of operation, substrate scope, and selectivity toward tertiary C−H centers, the method appears competitive with other C−H hydroxylation processes.