作者:L.V. Sudha、D.N. Sathyanarayana
DOI:10.1016/0022-2860(84)85326-0
日期:1984.11
The 270 MHz $^1H$-NMR and IR spectra of several N,N'-arylalkylureas are analysed in terms of their conformational properties. For most systems, the -NHCONH- group adopts a less energetic trans—cis conformation which is stabilized by unsymmetric intramolecular hydrogen bonding of lower polarizability, in contrast to other N,N'-disubstituted ureas which are predominantly found in the trans—trans form
分析了几种 N,N'-芳基烷基脲的 270 MHz $^1H$-NMR 和 IR 光谱,分析了它们的构象特性。对于大多数系统,-NHCONH- 基团采用能量较低的反式-顺式构象,与主要在反式-反式中发现的其他 N,N'-二取代脲相比,该构象通过较低极化率的不对称分子内氢键稳定. 强调了 N 取代基对氢键和分子构象的影响。