Doped Sol-Gel Materials as heterogeneous Reagents for Organic Synthesis

摘要

We advance the ue of reactive doped sol-gel materials as heterogeneous reagents for organic-chemistry synthesis. Three approaches were demonstrated with SiO_2-based materiasl: Direct physical entrapment of the organic reagent; in-situ generationof an inorganic reagent within the matrix; and covalent attachment of the reagent to the matrix.With the first, entrapped p-toluenesulfonic acid facilitated the 100% yield esterification of benzoic acid with 1-pentanol, and the 100% dehydration of 1-tetralol to 1,2-dihydronaphthalene; with the second approach, a sol-gel oxidant, SiO_2/MnO_2 was used to convert benzyl alcohol to benzaldehyde and 1-tetralol to 1-tetralone; and with the third, anchored propylamine facilitated dehydrobromination reactions resulting in double-bond formation.Several other reactions with these reagents are described, and their reactivities analyzed.