Pursuits for Metallomesogenic Materials Showing Spin-crossover Behavior

为了寻找在室温下表现出自旋交叉行为的介晶材料，已经进行了以下合成方法。具有目标性质的原型固体配合物的改性选择具有室温自旋交叉和滞后的铁（II）-氨基三唑配位聚合物作为原型，引入各种改性，例如用4-烷氧基亚苄基氨基取代配体上的4-氨基。迄今为止获得的所有样品已被证明含有至多三核物种，而不是介晶的。金属配合物和配体的设计评价（a）选择6配位三螯合物，希望获得某种低自旋材料。一个Ru（II）配合物可溶于环境温度向列相已获得使用烷基化，介晶配体。多吡啶配体也被新制备，以获得更强的配位场和多核功能。(b)[M（salen）]是多齿Schiff碱螯合物的单核配合物家族之一，其在过去已经产生了许多自旋交叉配合物，并且在本研究中通过接枝4至6个烷基链而衍生成多链介晶（M=Ni，Cu和VO）。在大多数情况下观察到柱状中间相。尝试用水或醇将上述离子配位化合物引入溶致中间相。已经成功地与聚醚接枝的扩展的芳香族化合物，它具有一个共同的两亲性的特点（但与倒置的中心-外围构造），并已在水中观察到的有色中间相。

The following synthetic approaches have been made in search for mesomorphic materials showing spin-crossover behavior at ambient temperatures.1. Modifications of Prototype Solid Complexes Exhibiting the Target PropertyIron(II)-aminotriazole coordination polymers exhibiting room temperature spin-crossover with hysteresis was selected as a prototype and various modifications were introduced such as substituting 4-amino group on the ligand with 4-alkoxybenzylideneamino group. All of the samples obtained so far have proven to contain at most trinuclear species and not mesomorphic either.2. Elaboration of the Designs for Metal Complexes and Ligands(a) 6-Coordinate tris-chelate complexes was then selected in the hope of obtaining somehow low-spin materials. A Ru(II) complex soluble in ambient temperature nematics has been obtained using an alkylated, mesogenic ligand. Polypyridyl ligands have also been prepared newly for stronger ligand fields and multinucleating functions.(b) [M(salen)] is among the family of mononuclear complexes of multidentate Schiff base chelates, which has produced a number of spin-crossover complexes in tha past, and in this study has been derivatized into polycatenar mesogens (M=Ni, Cu, and VO) by grafting 4 to 6 alkyl chains. Columnar mesophases have been observed in most cases.3. Attempts to Induce Lyotropic MesophasesAttempts were made to bring the above ionic coordination compounds into lyotropic mesophases with water or alcohols. Success has been made with a polyether-grafted extended aromatic compound, which has a common amphiphilic character (but with inverted center-periphery constitution), and the chromonic mesophase has been observed in water.