...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Crystal growth & design >New conformations and binding modes in halogen-bonded and ionic complexes of 2,3,5,6-tetra(2'-pyridyl)yoyrazine
【24h】

New conformations and binding modes in halogen-bonded and ionic complexes of 2,3,5,6-tetra(2'-pyridyl)yoyrazine

机译：2,3,5,6-四（2'-吡啶基）哒嗪的卤素键合和离子配合物中的新构象和键合模式

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

The enormous potential of 2,3,5,6-tetra(2'-pyridyl)pyrazine (tppz) as a versatile multisite component for the design and construction of complex structures is demonstrated by the preparation of several new complexes that possess previously unobserved binding modes and conformations. tppz forms halogen-bonded complexes with diiodine and organoiodides and forms ionic compounds in which tppz is either di- or tetraprotonated. We have prepared two new halogen-bonded complexes of tppz with diiodine and with tetraiodoethylene (TIE). Both possess extended chain structures of alternating donors and acceptors, with the tppz donors in the diiodine complex linked by two neutral -I(2)center dot I(2)center dot I-2- chains. Two new polyiodide complexes of tppz have also been prepared, one of which has di- and the other tetraprotonated cations. A bromide salt of the tetraprotonated tppz cation has also been prepared and found to be isomorphous with the known chloride salt. In the diiodine complex, tppz center dot 6I(2), the conformation of tppz is similar to that found in the metastable, tetragonal polymorph of the free donor, and obeying Ostwald's rule of stages, decomposes through solid-state loss Of 12 to give exclusively this polymorph. In the TIE complex, tppz center dot TIE, has a previously unreported conformation, but decomposes to the thermodynamically stable monoclinic polymorph upon loss of TIE. The diprotonated cation, [tppz(H)(2)](2+), which forms two intramolecular N-H center dot center dot center dot N hydrogen bonds and crystallizes with (I(2)center dot I-3)(-) anions, has a twisted conformation as opposed to the bowed conformation found for this cation with tetraphenylborate counterions. Tetraprotonated tppz hydrogen bonds to two iodide anions to form [tppz(H2I)(2)](2+) cations, similar to the bromide and chloride salts, but with triiodide anions rather than hydrated halides as in the lighter derivatives.
机译：2,3,5,6-四（2'-吡啶基）吡嗪（tppz）作为复杂结构设计和构建的通用多位组分的巨大潜力通过制备几种具有以前未观察到的结合的新配合物得到了证明模式和构象。 tppz与二碘和有机碘化物形成卤素键合的配合物，并形成其中tppz被二或四质子化的离子化合物。我们已经制备了tppz与二碘和四碘乙烯（TIE）的两种新型卤素键合配合物。两者都具有交替供体和受体的扩展链结构，二碘配合物中的tppz供体通过两条中性-I（2）中心点I（2）中心点I-2-链连接。还制备了两种新的tppz聚碘化物配合物，其中一种具有二-和另一种具有四质子化的阳离子。还已经制备了四质子化tppz阳离子的溴化物盐，发现与已知的氯化物盐同构。在二碘络合物tppz中心点6I（2）中，tppz的构象与在自由供体的亚稳态四方多晶型中发现的构象相似，并遵循Ostwald的分阶段规律，通过固态损失12分解，得到仅此多态。在TIE络合物中，tppz中心点TIE具有先前未报告的构象，但在TIE丢失后分解为热力学稳定的单斜晶型。双质子化阳离子[tppz（H）（2）]（2+）形成两个分子内NH中心点中心点中心点N个氢键并与（I（2）中心点I-3）（-）阴离子结晶与具有四苯基硼酸酯抗衡离子的该阳离子的弓形构象相反，其具有扭曲的构象。四质子化的tppz氢键与两个碘化物阴离子形成[tppz（H2I）（2）]（2+）阳离子，类似于溴化物和氯化物盐，但具有三碘化物阴离子而不是较轻的衍生物中的水合卤化物。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 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