Lewis Acidic Aluminosilicates: Synthesis, Al MQ/MAS NMR, and DFT-Calculated Al NMR Parameters.

Porous aluminosilicates are functional materials of paramount importance as Lewis acid catalysts in the synthetic industry, yet the participating aluminum species remain poorly studied. Herein, a series of model aluminosilicate networks containing [L-AlO] (L = THF, EtN, pyridine, triethylphosphine oxide (TEPO)) and [AlO] centers were prepared through nonhydrolytic sol-gel condensation reactions of the spherosilicate building block (MeSn)SiO with L-AlX (X = Cl, Me, Et) and [MeN] [AlCl] compounds in THF or toluene. The substoichiometric dosage of the Al precursors ensured complete condensation and uniform incorporation, with the bulky spherosilicate forcing a separation between neighboring aluminum centers.