Organometallics in zeolites and mesoporous silica

Both main group and transition metal organometallic compounds have been incorporated as guests in zeolite hosts. 

Ethylene polymerization catalysts can be made by incorporating methylalumox-ane or trimethylaluminum, AlMe, into zeolites, together with ( / -C5H5)2lVlCl2 (M = Ti, Zr) [208]. 

Trimethylgallium, GaMes, reacts with the surface Si-OH groups of the pores to form Mea-xGa moieties attached to the cavity surface, which further react with excess phosphine to produce intrazeolite GaP on heating [209], 

Transition metal organometallic guests in zeolite hosts have received considerably more attention than their main group counterparts. 

Group 6 metal (chromium, molybdenum, tungsten) carbonyls trapped in zeolites have been found to undergo partial thermal decomposition to produce M(CO)3 species which react with phosphines, polyolefins, and arenes to form the expected complexes, e.g. ( / -C6H6)Cr(CO)3 [210]. 

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