Conformational analysis of meso- and (±)-2,3-dicyano-2,3- dicyclopropylbutane and 1,2-dicyanotetracyclopropylethane

阅读量:

12

摘要:

The dipole moments of meso-2,3-dicyano-2,3-dicyclopropylbutane meso-1, (±)-2,3-dicyano-2,3-dicyclopropylbutane (±)-1 and 1,2-dicyanotetracyclopropylethane 2 in carbon tetrachloride and benzene have been measured over a range of temperatures. Analyses of the relative permittivity data show that at 25°C, meso-1 and (±)-1 favour the trans form. However, replacement of the methyl groups in 1 with cyclopropyl moieties completely reverses the transgauche equilibrium, such that 2 exists in 74% gauche conformation. The experimentally derived values of the energy difference between the gauche and trans conformers and the gauche/trans population quotients were compared with values predicted by molecular orbital calculations. Theory predicts that the conformational preference of the substituted dicyanoethanes is strongly influenced by solvent polarity. The crystal and molecular structures of meso-1 and 2 were determined by single-crystal X-ray diffraction methods. Both compounds exist in the trans conformation in the solid state.

展开

DOI:

10.1039/b103740b

被引量:

4

年份:

2001

通过文献互助平台发起求助,成功后即可免费获取论文全文。

我们已与文献出版商建立了直接购买合作。

你可以通过身份认证进行实名认证,认证成功后本次下载的费用将由您所在的图书馆支付

您可以直接购买此文献,1~5分钟即可下载全文,部分资源由于网络原因可能需要更长时间,请您耐心等待哦~

身份认证 全文购买

相似文献

参考文献

引证文献

来源期刊

引用走势

2010
被引量:2

辅助模式

0

引用

文献可以批量引用啦~
欢迎点我试用!

引用