Conversion of Disilanes to Functional Monosilanes. XIII. The Palladium Catalyzed Reductive Coupling of Benzylidene Dichlorides and Benzylidyne Trichlorides Using Disilanes as Reducing Agents
The reaction of benzylidene dichlorides or benzylidyne trichlorides with 1,2-dichloro-1,1,2,2-tetramethyldisilane or hexamethyldisilane proceeded smoothly in the presence of acatalytic amount of Pd(PPh3)4 to give (E)-stilbenes or (E)- and (Z)-α,β-dichlorostilbenes in high yields, respectively. Also, in the presence of the palladium(0) catalyst, α,α-dichlorobenzyltrimethylsilanes reacted with hexamethyldisilane yielding (E)-α,β-bis(trimethylsilyl)stilbenes in quantitative yield.
An Electroreductive Approach to Radical Silylation via the Activation of Strong Si–Cl Bond
作者:Lingxiang Lu、Juno C. Siu、Yihuan Lai、Song Lin
DOI:10.1021/jacs.0c10899
日期:2020.12.23
In this context, reactions mediated by silyl radicals have become increasingly attractive but methods for accessing these intermediates remain limited. We present a new strategy for silyl radical generation via electroreduction of readily available chlorosilanes. At highly biased potentials, electrochemistry grants access to silyl radicals through energetically uphill reductive cleavage of strong
The first inter- and intramolecular McMurry reactions of aroyltrimethylsilanes to substituted 1,2-bis(trimethylsilyl)ethene derivatives 2a-c and 7 are described. A low-valenttitanium reagent prepared by the reduction of TiCl3 with Na on inorganic supports (Al2O3, NaCl, TiO2) turned out to be best suited. Depending on the reaction conditions and on the particular substitution patterns of the substrates
描述了芳基三甲基硅烷与取代的1,2-双(三甲基甲硅烷基)乙烯衍生物2a-c和7的第一分子间和分子内McMurry反应。事实证明,通过在无机载体(Al 2 O 3,NaCl,TiO 2)上用Na还原TiCl 3制备的低价钛试剂是最合适的。根据反应条件和底物的特定取代方式,导致形成C,O-二甲硅烷基烯醇醚的中间体1,2-二甲硅烷基化的1,2-二醇钛酸酯的Brook重排可能与McMurry竞争脱氧途径。
Pd Nanoparticle-Catalyzed Stereospecific Mizoroki–Heck Arylation of <i>cis</i>-1,2-Disilylarylethylenes
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