Journal of Chromatography A ( IF 4.1 ) Pub Date : 2020-06-22 , DOI: 10.1016/j.chroma.2020.461366 Yujie Zhang 1 , Renling Lu 2 , Ming Chen 2 , Shouyong Zhou 3 , Dabing Zhang 4 , Haifeng Han 5 , Mingliang Zhang 5 , Hongdeng Qiu 6
An alternative method for efficient synthesis of urea-functionalized silanes was proposed on the basis of an N, N’-carbonyldiimidazole-mediated acyl-transfer reaction between various amino-containing building blocks. The employment of different parent aminosilanes and alkylamines afforded an array of urea-containing silanes, which were subsequently immobilized onto silica gel to form corresponding urea-embedded alkyl stationary phases for high-performance liquid chromatography. The different substituents on the silicon core of the derivatized silane were found to significantly influence the final chromatographic behaviors. The comparative chromatographic characterization of thus-prepared silica packings with conventional octadecyl (C18) stationary phases revealed that the urea group was beneficial to suppress silanol activity towards basic probes, as well as to increase the water-compatibility of the alkyl stationary phases. The combination of a polar urea moiety and a non-polar long alkyl chain was favorable for an enhanced steric selectivity towards shape-constrained isomers. The polarizability-sensitive feature of such stationary phases made them good candidates for efficient separation of nitro-containing polar substances.
中文翻译:
用于脲官能化硅烷的高效酰基转移方法及其作为液相色谱固定相固定在硅胶上的方法。
在N,N'的基础上,提出了另一种有效合成脲官能化硅烷的方法-羰基二咪唑介导的各种含氨基结构单元之间的酰基转移反应。使用不同的母体氨基硅烷和烷基胺可提供一系列含脲的硅烷,然后将其固定在硅胶上以形成相应的脲嵌入的烷基固定相,用于高效液相色谱。发现衍生化硅烷的硅核上的不同取代基会显着影响最终色谱行为。如此制备的具有常规十八烷基(C18)固定相的硅胶填料的比较色谱表征表明,脲基有利于抑制硅烷醇对碱性探针的活性,并有助于提高烷基固定相的水相容性。极性脲基团和非极性长烷基链的组合有利于提高对形状受限的异构体的空间选择性。这种固定相对极化率敏感的特性使其成为有效分离含硝基极性物质的良好选择。