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
Synergistic Visible-Light Photoredox/Nickel-Catalyzed Synthesis of Aliphatic Ketones via N–C Cleavage of Imides
作者:Javad Amani、Rauful Alam、Shorouk Badir、Gary A. Molander
DOI:10.1021/acs.orglett.7b00989
日期:2017.5.5
An electrophilic, imide-based, visible-light-promoted photoredox/Ni-catalyzed cross-coupling reaction for the synthesis of aliphatic ketones has been developed. This protocol proceeds through N–C(O) bond activation, made possible through the lower activation energy for metal insertion into this bond due to delocalization of the lone pair of electrons on the nitrogen by electron-withdrawing groups.
Direct <i>N</i>-Acylation of Lactams, Oxazolidinones, and Imidazolidinones with Aldehydes by Shvo’s Catalyst
作者:Jian Zhang、Soon Hyeok Hong
DOI:10.1021/ol302087z
日期:2012.9.7
Direct N-acylation of lactams, oxazolidinones, and imidazolidinones was achieved with aldehydes by Shvo's catalyst without using any other stoichiometric reagent. The N-acylations with alpha,beta-unsaturated aldehydes were achieved with excellent yields.
ISHIDA A.; BANDO T.; MUKAIYAMA T., CHEM. LETT., 1976, NO 7, 711-714