Li B,
*,
Bemish R,
Buzon RA,
Chiu CK.-F,
Colgan ST,
Kissel W,
Le T,
Leeman KR,
Newell L,
Roth J.
Pfizer Global Research and Development, Groton, USA
Aqueous Phosphoric Acid as a Mild Reagent for Deprotection of the
t-Butoxycarbonyl Group.
Tetrahedron Lett. 2003;
44: 8113-8115
Key words
phosphoric acid - deprotection -
tert-butoxycarbonyl group - peptide synthesis
Significance
Protecting groups play an essential role in organic synthesis. Among them, the tert-butoxycarbonyl (Boc) protecting group is unique and widely used in synthetic chemistry. Hence, there is a high demand for the development of simple and mild methods for the protection and deprotection of Boc groups. In 2003, the authors found aqueous phosphoric acid to be a mild reagent for the deprotection of the Boc group.
Comment
Aqueous phosphoric acid is efficiently used for the deprotection of the Boc group in various Boc-protected amine compounds. This protocol is mild, practically simple, and showcases high functional group tolerance. Furthermore, it preserves the stereochemical integrity of N-Boc amino acids.
