One-pot conversion of benzyl carbamates into fluorenylmethyl carbamates

A simple one-pot procedure smoothly converted N-benzyloxycarbonyl groups into N-fluorenylmethoxycarbonyl groups via hydrogenation with a poisoned catalyst in the presence of Fmoc-OSu. Functional groups such as t-butyl esters, t-butyl ethers, and N-Boc were stable under the reaction conditions.