Friedel-Crafts α-Aminoacylation of Aromatic Compounds with a Chiral N-Carboxy-α-amino Acid Anhydride (NCA); Part 2
作者:Osamu Itoh、Akira Amano
DOI:10.1055/s-1999-3405
日期:1999.3
The N-carboxy-α-amino acid anhydrides (NCA) derived from L-Asp(OEt), L-Glu(OMe), L-Met, and L-Pro reacted with aromatic compounds (toluene or benzene) in the presence of AlCl3, to afford the corresponding α-aminoalkyl aryl ketones as hydrochloride salts in moderate yields. The β- and γ-amino acid esters, which were obtained from the reaction of the aromatic compounds with L-Asp(OEt)- and L-Glu(OMe)-NCA, were hydrolyzed by hydrochloric acid to the corresponding β- and γ-amino acids as hydrochloride salts. L-Phe-NCA did not react with benzene in the presence of AlCl3, instead an intramolecular acylation occurred to afford (S)-2-aminoindanone hydrochloride. The chiralities of the original L-α-amino acids were most retained during these α-aminoacylation.
由L-天冬氨酰乙酯(L-Asp(OEt))、L-谷氨酰甲酯(L-Glu(OMe))、L-蛋氨酸(L-Met)和L-脯氨酸(L-Pro)衍生的N-羧基-α-氨基酸酐(NCA)在AlCl3存在下与芳香化合物(甲苯或苯)反应,以中等产率得到了相应的α-氨基烷基芳基酮的盐酸盐。由芳香化合物与L-天冬氨酰乙酯-NCA和L-谷氨酰甲酯-NCA反应得到的β-和γ-氨基酸酯,在盐酸作用下水解为相应的β-和γ-氨基酸的盐酸盐。L-苯丙氨酰-NCA在AlCl3存在下不与苯反应,而是发生分子内酰化反应,得到(S)-2-氨基茚满酮盐酸盐。在这些α-氨基酰化反应中,原始L-α-氨基酸的手性大部分得以保留。