Catalytic asymmetric cleavage of sp3 C-N bonds for access to highly enantioenriched N-benzylic sulfonamides

In the presence of 10 mol% of a chiral phosphoric acid, a variety of racemic N-benzylic sulfonamides having N-(3-indolyl)methyl groups smoothly undergo kinetic resolution with benzyl thiol at 0 degrees C or at room temperature and the remaining sulfonamides are recovered in moderate to excellent yields and with excellent ee.