(2)-Phosphonio and (2)-arsonio ethoxy-carbonyl cpds. - for introducing protecting groups into amino and hydroxy cpds. e.g. amino acids or peptides

摘要

New acyloxyethyl-phosphonium and -arsonium salts are cpds. of the formula: R1R2R3Y+-CH2-CH2-O-CO-X X- (I). In this formula, Y is P or As. R1, R2 and R3 are aryl or alkyl. Z is an anion. X is a group displaceable by a hydroxyl or amino function (pref. Cl) or is the acylated hydroxyl or amino function of an organic substance. The gp. -CO-O-CH2CH2Y+R1R2R3 Z- acts as a protecting gp. for hydroxy and amino functions. (I; X = group displaceable by OH or amino function) are thus useful as agents for introducing this protecting group, while the remaining cpds. (I) are the protected organic amino or hydroxy cpds. The protecting group is particularly suitable for amino acids, peptides, and their derivs. The protecting groups can readily be removed under basic conditions. Examples describe prepn. of (I; Y = P, R1 = R2 = R3 = Ph, X = Z = Cl) and the reaction of this cpd. with L-leucine methyl ester and phenylalanine to give the corresp. N-protected amino acid derivs.