Dibromomethyl silane

Thus, only few reports were disclosed for the [1,3] Brook isomerization Utimoto, Oshima and coworkers have reported that the treatment of tert-butyldimethyl(dibromomethyl)silane 64 with LDA followed by the addition of an excess of benzaldehyde lead to the 1,3-diol monosilyl ether 66 via the intermediacy of lithium carbenoid 65 (equation 24) . The rate of isomerization was dependent on the solvent used and HMPA was found to be the best solvent. ... 

Takai, K., Kataoka, Y., Okazoe, T., Utimoto, K. Stereoselective synthesis of (E)-alkenylsilanes from aldehydes with a reagent prepared by chromium(ll) reduction of trimethyl(dibromomethyl)silane. Tetrahedron Lett. 1987, 28, 1443-1446. 

The successive reaction of (dibromomethyl)silanes with LDA (hthium diisopropyl-amide) and two equivalents of benzaldehyde gives 1,3-diol monosilyl ethers in good yield (Scheme 10.221) [574]. This tandem reaction would proceed via anionic 1,3-silyl migration of /l-lithioxyalkylsilane intermediate 152 and addition of the resulting lithium carbenoid to benzaldehyde. Thus, internal activation of the silicon-lithium alkoxide promotes nucleophilic addition of a-haloalkylsilanes. Similar tandem reactions of 2-trimethylsilyl-l,3-dithiane with aldehydes [575] and epoxides [576] have been reported. 

A convenient synthesis of a-hydroxysilanes from the reaction of trialkylboranes and lithium with trimethyl(dibromomethyl)silane followed by hydrogen peroxide oxidation has appeared [reaction (6)]. Phenylchloroboranes have been im-... 

Dibromomethyl(trimethyl)silane, (CH3)3SiCHBr2 (1). The reagent is prepared from CH2Br2 and (CH3)3SiCl. ... 

Lithium-Halogen Exchange. Reaction of (dibromomethyl)-trimethylsilane with n-butyllithium at — 110°C results in the formation of trimethylsilylbromomethyllithium. The silane and the -BuLi are added simultaneously in order to suppress side reactions. Treatment of the intermediate lithium reagent with chlorotrimethylsilane (eq 1) or mercury(II) bromide (eq 2) affords bis(trimethylsilyl)bromomethane or bis(trimethylsilyl-bromDmethyl)mercury, respectively. If the lithium reagent is... 

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