Novel local D-A interactions and physical properties in organic mixed crystals

研究了有机化合物混合晶体中的局部D-A相互作用和一些物理化学性质。研究的材料为三烯、氮烯、4-取代苄基醇和烷基脲的衍生物。发现了一种制备雷公藤甲醌/雷公藤甲对苯二酚混合晶体的新方法。测定了双-（溴甲基）三萜烯（双- brme - tpq）及其几种包合物的晶体结构。该化合物与双-（溴甲基）三甲对苯二酚（bis- brme - tphq）的混合晶体表现出局部D-A相互作用。发现了双（羟基）三甲烯的四元环型氢键体系和相变。从晶体结构的知识来看，它与羟基三苯的混合晶体具有有趣的介电性质。6,7-二甲氧基三tycene的晶体结构表明其不能形成TPQ/TPHQ型混合晶体。5,12-二氢-o-5,12-苯萘-1,4-二酮的x射线结构显示其与苯的包合物存在，这一结果表明，将客体从苯转变为其他甲基苯可能会在混合晶体中发生局部的D-A相互作用。对对取代苄基醇混合晶体的相变特征进行了详细的研究，研究了组分对相变特征的依赖以及同位素对相变行为的影响。这些结果有助于阐明化合物的过渡机制。在一系列烷基化合物中，辛烷基-尿素表现出一种新的相变，并伴有很大的焓变。辛烷基-尿素和庚基-尿素的混合晶体显示出一个非常依赖于其组成的过渡特征，这为过渡机理提供了有用的信息。

Local D-A interactions and some physical-chemical properties in mixed crystals of organic compounds were investigated. The materials studies were derivatives of triptycene, azulene, 4-substitutedbenzyl alcohols and alkyl urea.A new method of preparation of triptycenequinone (TPQ)/triptycenehydroquinone (TPHQ) mixed crystal was found. Crystal structures were determined for bis-(Bromomethyl)triptycene (bis-BrMe-TPQ) and its several clathrates. A mixed crystal of the compound with bis-(bromomethyl)triptycenehydroquinone (bis-BrMe-TPHQ) exhibited local D-A interaction.Four membered ring type H-bond systems and phase transition were found for bis-(hydroxy)triptycenes. From the knowledge of the crystal structure, an interesting dielectric property is expected for its mixed crystal with hydroxytriptycene.The crystal structure of 6,7-dimethoxytriptycene suggests that it cannot form a TPQ/TPHQ type mixed crystal. X-ray structure of 5,12-dihydro-o-5,12-benzenonaphthacne-1,4-dione revealed the presence of its clathrate with benzene and this result indicates that a local D-A interaction in a mixed crystal would be possible by changing the guest from benzene to other methyl-benzenes.For mixed crystals of p-substitutedbenzyl alcohols, composition dependence of the characteristics of the phase transitions, as well as an isotope effect on the transition behavior, were investigated in detail. These results contributed to elucidate the transition mechanism of the compounds.Among a series of alkyl-ures, octyl-urea exhibited a novel phase transition accompanied by a very large enthalpy change. Mixed crystals of octyl- and heptyl-urea were found to show a transition characteristic that was very dependent on the composition, giving useful information on the transition mechanism.