o-Nitroaniline functionalized resorcinarene octapodands 1–5 with pendant methyl, ethyl, pentyl, nonyl or 1-decenyl groups, respectively, were synthesized and their structural properties investigated using X-ray crystallography and NMR spectroscopy. The upper rim of each podand is identical containing flexible side arms, in which rotation around the -OCH2CH2N- linkers create excellent possibilities for polymorphism. Two conformational polymorphs of acetone solvate of 2 were identified containing different side arm orientation and crystal packing. Compound 1 crystallized from acetone and nitromethane yielding two pseudopolymorphs with different packing motifs. The longer alkyl chains of 3–5 lead to differences in solubility and induce amphiphilic properties, which were studied at the air–water interface using the Langmuir-film technique. Crystals of amphiphilic compound 5, which has hydrophobic alkyl tails at the lower rim and hydrophilic nitroaniline groups at the upper rim, showed an interesting packing motif with alternating aromatic and aliphatic layers. Versatile structures of the octapodands in solid state and in solution serve as an example of how conformational flexibility can be utilized in crystal engineering and creating self-assembling monolayer structures.
合成了分别带有甲基、乙基、戊基、壬基或 1-
癸烯基侧基的邻
硝基苯胺官能化
间苯二酚八足体 1-5,并使用 X 射线晶体学和核磁共振波谱研究了它们的结构性质。每个吊舱的上缘都是相同的,包含柔性侧臂,其中围绕-OCH2CH2N-连接体的旋转为多态性创造了极好的可能性。鉴定出2的
丙酮溶剂化物的两种构象多晶型物,其含有不同的侧臂方向和晶体堆积。化合物 1 从
丙酮和
硝基甲烷中结晶,产生两种具有不同堆积基序的假多晶型物。 3-5 的较长烷基链会导致溶解度差异并产生两亲性,这一点使用朗缪尔薄膜技术在空气-
水界面进行了研究。两亲性化合物 5 的晶体在下缘具有疏
水性烷基尾部,在上缘具有亲
水性
硝基苯胺基团,显示出具有交替芳香族和脂肪族层的有趣堆积图案。固态和溶液中八足体的多功能结构是如何在晶体工程和创建自组装单层结构中利用构象灵活性的一个例子。