In this work, we report the preparation, isolation, and characterization of a family of double-decker silsesquioxane architectures starting from the previously reported DDSQ-Me₂H₂ precursor, a mixture of cis and trans isomers. Using such a starting material results in a subsequent mixture of isomers when hydrosilylation reactions using DDSQ-Me₂H₂ and hydroxyalkyl-substituted alkenes catalyzed by Karstedt catalyst are performed. We describe a procedure to sequentially crystallize the two isomers from one another, affording a protocol potentially applicable to other closely related derivatives. The ability to access pure cis and trans isomers of double-decker silsesquioxanes may result in the preparation of new materials and polymers with well-defined properties. All resulting silsesquioxanes were characterized by multinuclear (¹H, ¹³C, and ²⁹Si) NMR spectroscopy, FT-IR, and HR-MS. Additionally, we report five crystal structures of geometrical isomers, including two cis forms described in the literature for the first time. This is a breakthrough in itself and sets a new strategy for obtaining such exiting organosilicon-based systems.

中文翻译：

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羟基烷基取代的双层倍半硅氧烷：有效分离顺式和反式异构体

_{在这项工作中，我们报告了从先前报道的 DDSQ-Me 2} H ₂前体（顺式和反式异构体的混合物）开始的双层倍半硅氧烷结构家族的制备、分离和表征。_{当使用由Karstedt催化剂催化的DDSQ-Me 2} H ₂和羟烷基取代的烯烃进行氢化硅烷化反应时，使用这样的起始材料导致随后的异构体混合物。我们描述了一种顺序结晶这两种异构体的程序，提供了一种可能适用于其他密切相关的衍生物的协议。访问纯顺式和反式的能力双层倍半硅氧烷的异构体可能会导致制备具有明确特性的新材料和聚合物。所有得到的倍半硅氧烷均通过多核 ( ¹ H、¹³ C 和²⁹ Si) NMR 光谱、FT-IR 和 HR-MS 进行表征。此外，我们报告了几何异构体的五种晶体结构，包括文献中首次描述的两种顺式形式。这本身就是一个突破，并为获得这种现有的有机硅基系统设定了新的策略。