...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Crystal growth & design >Odd-even effects: Diamondoid and quartz networks by bis(pyridylcarboxamido) alkanes containing alkyl chains with an odd number of -(CH2)- groups as spacers
【24h】

Odd-even effects: Diamondoid and quartz networks by bis(pyridylcarboxamido) alkanes containing alkyl chains with an odd number of -(CH2)- groups as spacers

机译：奇偶效应：由含有奇数个-（CH2）-基团烷基链的双（吡啶基甲酰胺基）烷烃构成的类金刚石和石英网络

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Crystal structures of the homologous series of bis(pyridylcarboxamido) alkane derivatives having an odd number of carbon atoms in the alkyl spacer were analyzed and found to exhibit interesting structural and physical properties which differ significantly from those of their even analogues. The even members of this series have shown a remarkable preference to form one- or two-dimensional structures via N-H?N or N-H?O hydrogen bonds, while the odd ones have preferably exhibited 4-fold interpenetrated 3D networks such as diamondoid or quartz topologies via N-H?N hydrogen bonds. The odd members of the series have been found to adopt twisted conformations, in contrast to the linear conformation of the even ones. The melting points of the odd analogues are found to be lower than those of corresponding even members when the attached group (R) is a phenyl. However, such a trend in MP values has not been observed when the R group is a 4-pyridyl or 3-pyridyl group. The densities of these materials are found to decrease systematically with an increase in chain length and did not exhibit any dependence on the odd and even number of the -CH_2- groups in the spacers.
机译：分析了在烷基间隔基中具有奇数碳原子的双（吡啶基羧酰胺基）烷烃衍生物的同源系列的晶体结构，发现它们显示出有趣的结构和物理性质，与它们的偶数类似物明显不同。该系列的偶数成员显示出显着的偏好，可通过NH3N或NH2O氢键形成一维或二维结构，而奇数个成员则优选具有4倍互穿的3D网络，例如类金刚石或石英拓扑通过NH？N氢键已发现该系列的奇数成员采用扭曲的构象，与偶数的线性构象相反。当连接的基团（R）是苯基时，发现奇数类似物的熔点低于相应的偶数成员的熔点。然而，当R基团是4-吡啶基或3-吡啶基时，尚未观察到MP值的这种趋势。发现这些材料的密度随着链长的增加而系统地降低，并且不表现出对间隔基中-CH_2-基团的奇数和偶数的任何依赖性。

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号