Lynch B, Glennon J D, Tröltzsch C, Menyes U, Pursch M, Albert K
Department of Chemistry, University College Cork, Cork, Ireland.
Anal Chem. 1997 May 1;69(9):1756-62. doi: 10.1021/ac960717y.
A new (-)-menthyl bonded silica phase has been prepared by hydrosilation of a hydride silica intermediate. The hydride silica intermediate was synthesized by the reaction of a monoalkoxysilane (CH(3))(2)SiH(OEt) with silica gel, yielding a relatively high surface coverage (4.4 μmol/m(2)) of SiH groups. This intermediate was then used successfully in the preparation of a monomeric (-)-menthyl bonded silica phase. The bonded phase produced has been used for the chromatographic separation of enantiomers in a reversed phase mode (chiral separations). Solid state (13)C and (29)Si CP-MAS NMR spectroscopy and DRIFT spectroscopy provides valuable information on the structure of the different surface species formed on silica after modification. The surface coverage of the hydride silica intermediate and of the final bonded silica phase produced are also determined. It is found that this modification procedure can exclusively produce a monomeric coverage of SiH groups on the silica surface and can further produce a final monomeric bonded organic silica phase for the separation of enantiomers.
通过氢硅化氢化物二氧化硅中间体制备了一种新型的（-）-薄荷基键合硅胶相。氢化物二氧化硅中间体是由单烷氧基硅烷（CH(3))(2)SiH(OEt)与硅胶反应合成的，产生了相对较高表面覆盖率（4.4 μmol/m(2)）的SiH基团。然后，该中间体成功用于制备单体（-）-薄荷基键合硅胶相。所制备的键合相已用于反相模式下对映体的色谱分离（手性分离）。固态（13）C和（29）Si CP-MAS NMR光谱以及DRIFT光谱提供了有关改性后二氧化硅上形成的不同表面物种结构的有价值信息。还测定了氢化物二氧化硅中间体和最终制备的键合硅胶相的表面覆盖率。发现这种改性方法可以在二氧化硅表面专门产生SiH基团的单体覆盖率，并可以进一步制备用于对映体分离的最终单体键合有机硅胶相。
