Organometallic Fluorides of Group-4 Metals as Efficient Catalysts for Polymerization

ORGANOMETALLIC FLUORIDES OF GROUP-4 METALS AS EFFICIENT CATALYSTS FOR POLYMERIZATION 

Another way to make the catalytically active metal center more Lewis acidic is to attach a highly electronegative center such as fluorine. We have been especially interested in the preparation of organometallic fluorides of Group-4 metals owing to their importance as polymerization catalysts. 

FIGURE 7 Shapes of the bonding orbitals around the metal centers in 19, 20, and 24 showing significant buildup of electron density on the oxygen atoms. Reprinted with permission from Refs. (32) and (47). 

FIGURE 8 Activity of CpTiX3/MAO (900) with X = Cl and F for polymerization of styrene at various temperatures in toluene. Reprinted with permission from Ref. (78). 

TABLE 9 Data Characterizing Comparative Styrene Polymerization  

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