Polypeptides. Part V. The use of t-butyl 2,4,5-trichlorophenyl carbonate in the synthesis of N-t-butoxycarbonyl amino-acids and their 2,4,5-trichlorophenyl esters
作者:Wallace Broadbent、J. S. Morley、B. E. Stone
DOI:10.1039/j39670002632
日期:——
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 N-t-butoxycarbonyl amino-acids (and 2,4,5-trichlorophenol) in excellent yield. By co-extraction of the N-t-butoxycarbonyl amino-acid and 2,4,5-trichlorophenol from the acidified reaction mixture, followed by treatment of the extracts with NN′-
碳酸叔丁酯2,4,5-三氯苯甲酸,方便地从光气中分两步制备,在碱的存在下与氨基酸干净地反应,得到N-叔丁氧羰基氨基酸(和2,4,5-三氯苯酚)的良率。由的共萃取Ñ -t丁氧羰基氨基酸及从所述酸化反应混合物2,4,5-三氯苯酚,接着处理所述提取物的具有NN '-dicyclohexylcarbodi酰亚胺,相应的高收率Ñ -t得到-丁氧基羰基氨基酸2,4,5-三氯苯基酯。这些活性酯大部分是稳定的结晶固体,可以方便地用于肽合成中。