A new, one-step and racemization-free synthesis of phthaloyl derivatives of α-amino carboxamides is described. Under ultrasound, α-amino carboxamides and dipeptide derivatives react with monomethyl phthalate in the presence of BOP, ZnCl2 and i-Pr2NEt to afford the corresponding N α -phthaloyl α-amino carboxamides or dipeptides in good to excellent yields. Cyclization of the intermediate N α -[(o-methoxycarbonyl)benzoyl]amino carboxamides to the desired products was very slow when the reaction was conducted either in the absence of ZnCl2 and/or without sonication, but the process was greatly accelerated when both ZnCl2 and ultrasound were used.
报道了一种新型一步合成方法,用于制备无消旋化的邻苯二甲酰衍
生物α-
氨基羧
酰胺类化合物。在超声波作用下,α-
氨基羧
酰胺类化合物和二肽衍
生物与单甲基
邻苯二甲酸酯在BOP、ZnCl2和i-Pr2NEt的存在下反应,以良好的至优异的产率得到相应的Nα-邻苯二甲酰α-
氨基羧酰胺或二肽。当中间体Nα-[(邻甲氧羰基)苯甲酰]
氨基羧
酰胺类化合物的环化反应在没有ZnCl2和/或不使用超声波的条件下进行时,反应速度非常慢,但当同时使用ZnCl2和超声波时,反应过程大大加速。