Polypeptides. Part V. The use of t-butyl 2, 4, 5-trichlorophenyl carbonate in the synthesis of Nt-butoxycarbonyl amino-acids and their 2, 4, 5-trichlorophenyl esters

W Broadbent, JS Morley, BE Stone

Index: Broadbent,W. et al. Journal of the Chemical Society [Section] C: Organic, 1967 , p. 2632 - 2636

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Citation Number: 25

Abstract

t-Butyl 2, 4, 5-trichlorophenyl carbonate, conveniently prepared from phosgene in two stages, reacts cleanly with amino-acids in the presence of bases to give Nt-butoxycarbonyl amino-acids (and 2, 4, 5-trichlorophenol) in excellent yield. By co-extraction of the Nt- butoxycarbonyl amino-acid and 2, 4, 5-trichlorophenol from the acidified reaction mixture, followed by treatment of the extracts with NN′-dicyclohexylcarbodi-imide, high yields of ...