HX Addition to Multiple Bonds

At 60°, chloroplatinic acid has been used to catalyze the hydrosilylation of butenes and the following activation energies were obtained butene-1 (1.40 kcal/mole), butene-2 (16.0 kcal/mole), and isobutene (32.0 kcal/ mole) 274). 

The exchange reaction of silanes has also been effectively catalyzed using a palladium-carbon heterogeneous catalyst. A good example of 

The reaction between olefins or acetylenes with silicon hydrides in the presence of phosphinenickel complexes has been studied for a variety of substituents on the phosphine and on the silane. In many cases two products are obtained, one of them is the expected simple adduct and the other is an adduct, the formation of which has involved an interchange of hydrogen and chlorine on silicon in the course of hydrosilylation (206) Eq. (90). When methyldichlorosilane was added to octene-1 at temperatures in excess of 120°, the two silanes obtained were CgHi7SiMeClH and CgHi7SiMeCl2. The results outlined in Table II 

Catalyst SiXaClH Total yield (%) CaHiaSiXaH/CsHiaSiXaCl 

Phenylacetylene did not form an adduct under similar conditions. The complex between 1,2-bis(dimethylphosphino)-1,2-dicarbaclosododeca-borane with nickel(II) chloride effectively catalyzed the hydrosilylation of olefins (209). Catalysis by this nickel complex differed, however, in that considerable amounts of internal adducts were formed  

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