Amide and lactam hydrolysis ofN-(2-hydroxyacetyl)-2-pyrrolidone: effective catalysis
作者:Lisaedy García Borboa、Oswaldo Núñez
DOI:10.1002/poc.1067
日期:2006.11
When N-(2-hydroxyacetyl)-2-pyrrolidone (open form) is dissolved in water at pH > 8, irreversible cleavage of the exocyclic and endocyclic amide CN bond occurs. The latter rupture corresponds to the lactam opening yielding N-(4-hydroxyacetyl)butanoic acid (NBA). NBA is produced from the ester hydrolysis of the ester-amide macrocycle that is in equilibrium with the cyclol form of the open form. We have
当将N-(2-羟乙酰基)-2-吡咯烷酮(开放形式)溶于pH> 8的水中时,环外和环内酰胺C N键发生不可逆的裂解。后者的破裂对应于内酰胺开口,产生N-(4-羟基乙酰基)丁酸(NBA)。NBA是由酯酰胺大环的酯水解产生的,该酯水解与开环形式的脂环形式处于平衡状态。我们先前已经报道了N-(2-氨基乙酰基)-2-内酰胺的后一种平衡。2-吡咯烷酮(内酰胺)和乙醇酸是通过酰胺外环裂解直接水解开环形式制得的。的[NBA] /在高pH值[内酰胺]比的增加,因为NBA生产是二阶相对于[OH -],而相应的内酰胺形成仅是一级的。因此,获得的球芯是分别产生内酰胺和NBA的速率常数的总和。该kobs未被催化,特定碱被催化,具有分别为2.1×10 -6 s -1和0.025 M -1 s -1的异常高的速率常数。形成的相应四面体中间体的稳定性和分子内烷氧基亲核对内酰胺羰基的攻击与内酰胺氮的有效质子化促进C N