Si–C attachment points during sol–gel synthesis of organosilicas from 2,8-bis-silylated Tröger's base as building block precursor

The porous organosilica framework containing Tröger's base (TB) prepared by mild sol–gel synthesis from 2,8-bis-silylated TB precursor contains a mixture of two point attached TB and one point attached TB units, resulting from unexpected partial Si–C bond cleavage as demonstrated by 29Si MAS NMR spectroscopy and by selective chemo-desorption of the anchored organic part of the hybrid material.