Using a new superparamagnetic nanocatalyst for the N-Boc protection of amines

Functional group protection and deprotection methods are important in the multistep organic synthesis. The presence of an amino group in various biologically active compounds makes its protection as a necessity during their synthesis [1]. The Namine protecting groups have been used extensively across a wide range of chemical fields, such as peptide, nucleotide, polymer, and ligand preparations. Several methods and reagents have been reported for the protection of amine and amin and amine derivatives [2]. Among them, N-tert-butoxycarbonylation has received the greatest attention because of the stability of the N-Boc group against nucleophilic attack or alkali media and catalytic hydrogenation [3]. The challenge of designing a protocol for efficient Boc protection of amines, which is mild as well as environment-friendly and which has the advantages of solid catalysts, encouraged us to investigate the applicability of a new stable and highly active superparamagnetic nanocatalyst for the preparation of N-Boc derivatives. In this regard, a simple, green, and efficient method for the N-tert-butoxycarbonylation of amines was accomplished at 50˚C and neat conditions. The green conditions, excellent yields, practicability, operational simplicity, product purity, cost efficiency and environmentally profits are the considerable advantages of this protocol.