Triisobutyl aluminum

Tricliloro-l, 2,2-trifluoroethane, 132 Tricresyl phosphates, 132 Tricyclohexyltin hydroxide, 132 Triethyl aluminum, 132 Triethylamine, 132 Triethyl phosphite, 132 Trifluorobromomethane, 132 Trifluoroethane, 132 Trifluoromethane, 132 Trifluralin, 132 Triisobutyl aluminum, 133 Trikem SA, 146... 

Titanium, vanadium or chromium oxides activated with chlorine-free organo-aluminum compounds, triethyl- or triisobutyl aluminum, have also been used as catalysts [285],... 

Lieflander and Stbber (218) treated Aerosil and other silicas with solutions of triisobutyl aluminum, Al(C4Hg)g, in heptane. After thorough washing with heptane, about 5.7 /itmole/m of aluminum remained on the surface. This figure agrees well with other reactions of the silanol groups. The reaction and subsequent hydrolysis were formulated as... 

TRIISOBUTYL- ALUMINUM Aluminum triisobutyl, TIBA, TIBAL Flammable Liquid 3 3 3 W... 

Vandenberg (77) has found that vinylethers are polymerized by combinations of vanadium tetrachloride and triethylaluminum. Vandenberg believed that the intermediate vanadium trichloride, produced by reduction of the vanadium tetrachloride, reacted with the triisobutyl-aluminum-tetrahydrofuran complex to produce the modified Friedel-Crafts catalysts that converted the vinylether to isotactic polymer. 

The effect of nucleophilic dienes on the copolymerization of ethylene and propylene has been reported by Gladding, Fisher and Collette (88). Table 8 shows that 1.4-hexadiene decreased the tendency for propylene to enter into the ethylene-propylene terpolymer, produced by a triisobutyl aluminum-vanadium oxychloride catalyst. 

Ashikari, Kanemitsu, Yanagisawa, Nakagawa, Okomoto, Ko-bayashi and Nishioko (59) have studied the copolymerization of propylene and styrene. They found decreasing styrene content and conversion of the copolymer by increasing aluminum to titanium ratios with triisobutyl aluminum and titanium trichloride catalysts. The trialkylaluminum titanium tetrachloride catalyst had relatively low steric control on the polymerization while trialkylaluminum-titanium trichloride had higher steric control. The ionicity which is required for atactic polymerization is more cationic for styrene than for propylene which is more cationic than that for ethylene. Some of the catalyst systems for these three monomers are shown on the ionicity chart in Fig. 9. 

Materials. Alkylaluminum compounds, supplied by Texas Alkyls, Inc., were used without further purification. Analytical data supplied by the manufacturer showed all alkyls to be of greater than 90% purity. The diisobutyl-aluminum hydride was prepared by heating the commercial triisobutyl-aluminum at 130° C. and pumping off the gases evolved. Analysis of the product showed 16.8% aluminum as compared to the theoretical value of 18.97%. 

The polymerization of cyclopentadiene with triisobutyl aluminum-titanium tetrachloride catalyst system is reported (7) to yield polycyclopentadiene with 1,4- structure. Apparently the polymerization of cyclopentadiene is analogous to that of butadiene, wherein, as shown in Table I, in a TiC catalyst system, AIR3 yields a 1,4- structure and LiAlH4 yields a 1,2- structure. 

A selective reduction of keto groups is possible in the presence of epoxides using triisobutyl-aluminum at low7 temperatures153. Thus, 2,3-epoxy-4,4-dimethylcyclohexanone is reduced with good stereoselectivity [d.r. (cis/trans) 5 95] to fr[Pg.822]

R)-2-endof-endo-3-Amino-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ol (11) (91 %) is isolated from (1 ft)-cWo-3-amino-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one (10) with isobutylaluminum dichloride (prepared from triisobutyl aluminum and aluminum trichloride)196. 

---