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化学学报
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化学学报 ›› 2011, Vol. 69 ›› Issue (11): 1354-1360. 上一篇    下一篇

研究论文

a-单取代-1,2-环十二二酮单肟的合成及晶体结构

陈守聪，张春艳，张莉，王道全，王明安*   

  1. (中国农业大学应用化学系 北京 100193)
  • 投稿日期:2010-11-11 修回日期:2010-12-27 发布日期:2011-02-17
  • 通讯作者: 王明安 E-mail:wangma@cau.edu.cn
  • 基金资助:

    国家自然科学基金

Synthesis and Crystal Structure of Novel a-Monosubstituted Cyclododecan-1,2-dione Monooxime

Shou-Cong Chen 2,2,Wang Ming-An2   

  1. (Department of Applied Chemistry, China Agricultural University, Beijing 100193)
  • Received:2010-11-11 Revised:2010-12-27 Published:2011-02-17
  • Contact: Wang Ming-An E-mail:wangma@cau.edu.cn

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通过a-单取代环十二酮与亚硝酰氯反应合成了一系列a-单取代-1,2-环十二二酮单肟, 它们的结构经1H NMR, 13C NMR, ESI-MS和元素分析确证. X射线衍射和量子力学计算结果表明, a-单取代环十二酮与亚硝酰氯反应生成a-单取代-1,2-环十二二酮单肟时, 生成产物具有[4233]-3-酮和[3333]-2-酮两种不同类型的优势构象, a-取代基位于边碳外向位或角碳反向位, 两种构象中C＝N双键和羰基均处在边碳上, 位于环的两侧, 它们的二面角介于162°～174°之间, 肟的C＝N双键均为E式, 两种不同的低能构象在溶液中可以通过C2-假旋相互转化, 在形成晶体的过程中则分别采取能量最低的优势构象. 结构特征分析表明, p-p和p-p相互作用可能是导致a-取代-1,2-环十二二酮单肟的十二元环骨架构象改变的主要因素.

关键词: a-单取代-1,2-环十二二酮单肟, X射线衍射, 量子力学计算, 构象分析

A series of a-monosubstituted cyclododecan-1,2-dione monooxime were prepared by the reaction of a-monosubstituted cyclododecanone and nitrosyl chloride, and their structures were confirmed by the 1H NMR, 13C NMR, ESI-MS and elemental analysis data. X-ray diffraction and quantum mechanics calculation results showed that the products take two different [4233]-3-one and [3333]-2-one conformation, a-substituted groups present at a-side-exo or a-corner-anti position, the C＝N and C＝O double bonds present at side chain with the torsion angles in the range of 162°～174°, and the C＝N double bond of oximes have E-configuration when they are synthesized with the reaction of a-monosubstituted cyclododecanone and nitrosyl chloride. These two different conformations exist in a dynamic equilibrium with the C2-pseudorotation transferring pathway in the solution, and the preferred conformation was taken when it crystallized from the solution. The analysis of structure characteristics indicated that p-p and p-p interaction may be the main factor which makes the skeleton conformation change of the twelve-membered ring of a-monosubstituted cyclododecan-1,2-dione monooxime.

Key words: a-monosubstituted cyclododecan-1,2-dione monooxime, X-ray diffraction, quantum mechanics calculation, conformation analysis