tert-Butoxycarbonyl Chloride for the Introduction of N-Boc Groups into Amino Acids

Abstract

tert-Butoxycarbonyl chloride (BocCl) can be generated in situ from tert-butyl alcohol, COCl₂, and pyridine at -74 ˚C to introduce the Boc group in high yield into a hindered amino acid. The method is suitable for large-scale preparations of Boc-amino acids.

Key words

Boc chloride - COCl₂ - pyridine - mixed anhydrides - amino acids

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