Synthesis of an [(NHC)<sub>2</sub>Pd(SiMe<sub>3</sub>)<sub>2</sub>] Complex and Catalytic<i>cis</i>-Bis(silyl)ations of Alkynes with Unactivated Disilanes
作者:Melvyn B. Ansell、Debbie E. Roberts、F. Geoffrey N. Cloke、Oscar Navarro、John Spencer
DOI:10.1002/anie.201501764
日期:2015.5.4
The novel complex cis‐[(ITMe)2Pd(SiMe3)2 (ITMe=1,3,4,5‐tetramethylimidazol‐2‐ylidene) has been synthesized by mild oxidative cleavage of Me3SiSiMe3 using [(ITMe)2Pd0]. The use of this complex as precatalyst for the cis‐bis(silyl)ation of alkynes using unactivateddisilanes is reported.
Addition reactions of methoxymethyldisilanes to phenylacetylene in the presence of various triphenylphosphine complexes of Ni, Rh, Pd and Pt were investigated. Palladium and platinumcomplexes, Pd(PPh3)4, PdCl2(PPh3)2 and Pt(PPh3)4 were found to be effective catalysts for the double silylation, giving adducts, cis-α,β-disilylated styrene derivatives selectively. It also was shown that hexamethyldisilane
lenes undergo with aryl iodides a stereospecific Mizoroki–Heck arylation leading to trans-ditrimethylsilyldiarylethylenes. This chemoselectivity is in contrast to that of their trimethylgermyl analogues, which are arylated at the position of the C–Ge bonds. trans-1,2-Ditrimethylsilylarylethylenes are completely unreactive under the standard reaction conditions. The reaction tolerates the presence of
Stereoselective palladium-catalyzed synthesis of (Z)-trimethyl(2-arylethenyl)silanes by arylation of (E)-1,2-bis(trimethylsilyl)ethylene. Effects of added halides compared to silver salts
作者:Kostas Karabelas、Anders Hallberg
DOI:10.1021/jo00268a058
日期:1989.3
Palladium(II) acetate-tert-alkyl isocyanide as a highly efficient catalyst for the inter- and intramolecular bis-silylation of carbon-carbon triple bonds