Müller Petra U, Weber Edwin, Rheinwald Gerd, Seichter Wilhelm
Institut für Organische Chemie, Technische Universität Bergakademie Freiberg, Leipziger Str. 29, D-09596, Freiberg/Sachsen, Germany.
Org Biomol Chem. 2005 Oct 21;3(20):3757-66. doi: 10.1039/b509917j. Epub 2005 Sep 12.
Based on the principle of supramolecular preorganization, a new type of oligofunctional amphiphile, of which compounds 1-4 are representative structures, has been designed and synthesized. The typical feature of their structure is a highly rigid and geometrically well-defined central unit composed of ethynylene substituted aromatic spacers with different numbers of amphiphilic segment groups (also of a rigid geometric design) attached to it. The molecules form well-defined Langmuir films when spread from a solution at the air/water interface or when a 10(-4) M aqueous CaCl2 solution was used as the subphase. By analysis of the surface pressure-surface area (pi-A) isotherms, information on the packing behavior and orientation of the amphiphilic molecules depending on the molecular structure could be obtained. Morphological characterization of the dynamic process of monolayer compression at the air/water interface was carried out by Brewster angle microscopy, illustrating several phase states visualized as snap shots. Thin monolayer films produced on a 10(-4) M aqueous CaCl2 subphase can be transferred to a mica solid support by the Langmuir-Blodgett technique. Tapping mode atomic force microscopy reveals a surface topography of the monofilms composed of 1 and 3 that differ in roughness and also in the properties of elasticity, hardness and adhesive strength. X-Ray crystal structure analysis of three relevant intermediate compounds of the synthesis were successfully determined giving an indication of the potential structural features inherent in the new amphiphiles.
基于超分子预组织原理，设计并合成了一种新型的多官能团两亲分子，其中化合物1 - 4为代表性结构。它们结构的典型特征是一个高度刚性且几何形状明确的中心单元，由乙炔基取代的芳族间隔基组成，其上连接有不同数量的两亲链段基团（同样具有刚性几何设计）。当从空气/水界面的溶液中铺展时，或者当使用10⁻⁴ M的氯化钙水溶液作为亚相时，这些分子会形成明确的朗缪尔膜。通过分析表面压力 - 表面积（π - A）等温线，可以获得关于两亲分子根据分子结构的堆积行为和取向的信息。利用布鲁斯特角显微镜对空气/水界面单层压缩的动态过程进行形态学表征，展示了几个可视作快照的相态。在10⁻⁴ M的氯化钙水溶液亚相上制备的薄单层膜可以通过朗缪尔 - 布洛杰特技术转移到云母固体支持物上。敲击模式原子力显微镜揭示了由化合物1和3组成的单分子膜的表面形貌，它们在粗糙度以及弹性、硬度和粘附强度等性质方面存在差异。成功测定了合成过程中三种相关中间化合物的X射线晶体结构，这表明了新型两亲分子固有的潜在结构特征。
