Development of a novel protocol for chemoselective deprotection of N / O -benzyloxycarbonyl (Cbz) at ambient temperature

A novel protocol for the deprotection of N -benzyloxycarbonyl and O -benzyloxycarbonyl groups by nickel boride generated in situ from NaBH 4 and NiCl 2 ·6H 2 O in methanol at room temperature has been developed to give the corresponding amines and phenols. This protocol is chemoselective as groups like chloro, bromo, amide, ester, pyridine, and tert-butyloxycarbonyl moiety are unaffected under these conditions. The deprotection has also been validated in gram scale reactions, to establish the wider appropriateness of this protocol. Graphical abstract