Chloroplatinic acid—Triethylsilane

Chloroplatinic acid-Triethylsilane. H2PtCl4-(C2H5)3SiH. 

Pitt and Skillem (23) observed H/vinyl exchange during the addition of triethylsilane to vinyldimethylchlorosilane catalyzed by chloroplatinic acid [Eq. (29)]. 

The main product in hydrosilation of a,P-unsaturated ketones and aldehydes catalyzed by chloro-platinic acid, platinum on alumina, or metallic nickel is the corresponding silyl enol ether. With nickel catalyst, product distribution is highly dependent on the enone structure. Hydridosilanes add to a, -unsaturated esters, producing the corresponding silyl enolate as well as carbon silylated products. The course of addition depends on substrate structure and the hydridosilane utilized. Thus, triethylsilane undergoes 1,4-addition to methyl acrylate in the presence of chloroplatinic acid, while trichlorosilane with either chloroplatinic acid or Pt/C gives the -silyl ester (Scheme 65). ... 

This approach was successfully applied to the total synthesis of ( )-niuscone. Treatment of the a,p-and p,7-enone mixture (Scheme 66) with triethylsilane in refluxing glyme containing catalytic amounts of chloroplatinic acid afforded 1-triethylsilyloxycyclotetradecene. TTie two isomeric enones rapidly equilibrate under these conditions. 

Among the many available procedures for preparing alkenylsilanes are hydrosilylation of alkynes and partial reduction of alkynylsilanes. Hydrosilylation of 1-alkynes with triethylsilane in the presence of catalytic chloroplatinic acid results in regioselective... 

Triethylsilane and aq. dioxane refluxed with chloroplatinic acid in isopropanol triethylsilanol. Y 90%. E. Y. Lukevits et al., Dokl. Akad. Nauk SSSR 145, 806 (1962) G. A. 58, 1485e. 

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