Practical metal-free C(sp(3))-H functionalization: construction of structurally diverse α-substituted N-benzyl and N-allyl carbamates.

Described is a practical and universal CH functionalization of readily removable N-benzyl and N-allyl carbamates, with a wide range of nucleophiles at ambient temperature promoted by Ph3 CClO4 . The metal-free reaction has an excellent functional-group tolerance, and displays a broad scope with respect to both N-carbamates and nucleophile partners (a variety of organoboranes and CH compounds). The synthetic utility in target- as well as diversity-oriented syntheses is demonstrated.