Chinese Journal of Organic Chemistry ›› 2004, Vol. 24 ›› Issue (5): 554-557. Previous Articles     Next Articles

α-单取代环十二酮构象转换的溶剂效应和温度效应

王明安, 梁晓梅, 韩翔宇, 马祖超, 王道全   

  1. 中国农业大学应用化学系 北京 100094
  • 收稿日期:2003-07-17 修回日期:2003-10-16 接受日期:2003-11-14 发布日期:2022-09-20
  • 基金资助:
    国家自然科学基金(No. 20072053)资助项目

Effects of Solvent and Temperature on the Conformational Interconversion of α-Monosubstituted Cyclododecanones

WANG, Ming-An, LIANG, Xiao-Mei, HAN, Xiang-Yu, MA, Zu-Chao, WANG, Dao-Quan   

  1. Department of Applied Chemistry, China Agricultural University, Beijing 100094
  • Received:2003-07-17 Revised:2003-10-16 Accepted:2003-11-14 Published:2022-09-20
  • Contact: *E-mail: wangdq@cau.edu.cn

The effects of the solvent and temperature on the interconversion between the α-side-exo-substituted[3333]-2-one (A) and α-corner-syn-substituted[3333]-2-one (B) conformations of the α-monosubstituted cyclododecanoneshave been studied by means of 1H NMR technology. The result shows that increasing the polarity of the solvent generally increases the population of the conformation B owing to the higher dipole moment of the conformation B than that of A. By contrast, in the case of the monosubstituted cyclododecanones with an intramolecular hydrogen bondbetween the substituent and the carbonyl group, increasing the polarity of thesolvent decreases the population of the conformation B owing to the weakening of the intramolecular hydrogen bond. The result also shows thatraising temperature is favourable to the interconversion of two conformations,achieving a new equilibrium.

Key words: α-monosubstituted cyclododecanone, conformation, conformational interconversion, α-side-exo-substituted[3333]-2-one conformation, α-corner-syn-substituted[3333]-2-one conformation