Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy.
Department of Industrial Chemistry "Toso Montanari", University of Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy.
Int J Mol Sci. 2020 Oct 30;21(21):8124. doi: 10.3390/ijms21218124.
The chiral ()-10-hydroxystearic acid (()-10-HSA) is a positional homologue of both ()-12-HSA and ()-9-HSA with the OH group in an intermediate position. While ()-12-HSA is one of the best-known low-molecular-weight organogelators, ()-9-HSA is not, but it forms crystals in several solvents. With the aim to gain information on the structural role of hydrogen-bonding interactions of the carbinol OH groups, we investigated the behavior of ()-10-HSA in various solvents. This isomer displays an intermediate behavior between ()-9 and ()-12-HSA, producing a stable gel exclusively in paraffin oil, while it crystallizes in other organic solvents. Here, we report the X-ray structure of a single crystal of ()-10-HSA as well as some structural information on its polymorphism, obtained through X-ray Powder Diffraction (XRPD) and Infrared Spectroscopy (IR). This case study provides new elements to elucidate the structural determinants of the microscopic architectures that lead to the formation of organogels of stearic acid derivatives.
（)-10-羟基硬脂酸（()-10-HSA）是()-12-HSA 和()-9-HSA 的位置同系物，其 OH 基团处于中间位置。虽然()-12-HSA 是众所周知的低分子量有机凝胶剂之一，但()-9-HSA 不是，但它在几种溶剂中形成晶体。为了获得关于仲醇 OH 基团氢键相互作用的结构作用的信息，我们研究了()-10-HSA 在各种溶剂中的行为。这种异构体在()-9 和()-12-HSA 之间表现出中间行为，仅在石蜡油中产生稳定的凝胶，而在其他有机溶剂中结晶。在这里，我们报告了（)-10-HSA 的单晶的 X 射线结构以及通过 X 射线粉末衍射（XRPD）和红外光谱（IR）获得的其多态性的一些结构信息。这个案例研究提供了新的元素来阐明导致硬脂酸衍生物形成有机凝胶的微观结构的结构决定因素。
