Increasingly more complex non-hydrolytic sol-gel schemes were reported by Ghosh et al., Clark et al., Lee et al., Clark and Barnes, and Barnes et al., utilizing TiCl4, Cp2TiCl2, ZrCl4, Cp2ZrCl2, VOCl3, WOCl4, and AlCl3 as metal sources and SiCl4, HSiCl3, MeSiCl3, and Me2SiCl2 as inert cross-linkers. This line of research has culminated in a flexible two-step, one-pot procedure (Figure ). The CUBE building block is first cross-linked by a limited amount of the metal precursor, providing ideal conditions for M-X group condensation, homogeneous incorporation of the metal sites, and structural relaxation. A true solution of oligomeric species is formed, which are then "knitted" together by further cross-linking with silyl chlorides to produce porous silicate matrices. The solvent and all reaction byproducts are then removed under vacuum to obtain pure materials. Subsequently, Stýskalík et al. used the approach to prepare a series of porous Lewis acidic aluminosilicate matrices containing