Chlorobis phosphane

Dichloro(trifluorovinyl)phosphane and chlorobis(trifluorovinyl)phosphane react with anti-mony(V) fluoride at room temperature undergoing not only substitution of chlorine but also addition of two fluorine atoms to the phosphorus to give tetrafluoro(trifluorovinyl)-A5-phos-phane and trifluorobis(trifluorovinyl)-A5-phosphane, respectively.100... 

The method has been further improved." Trimethyl(perfluoroalkyl)silanes RpTMS (Rp = c, -C, perfluoroaliphatic groups) are prepared by reaction of perfluoroalkyl halides RpX (X = Br, I) with chlorotrimethylsilane in the presence of tris(dialkylamino)phosphanes in acetonitrile. For example, chlorotrimethylsilane was treated with bromotrifluoromethane and tris(diethylamino)phosphane in acetonitrile at — 40"C for 1 hour to give trimethyl(trifluo-romethyl)silane in 90% yield. Bis(dimethylamino)(trifluoromethyl)silane is available from the reaction of chlorobis(dimethylamino)silane with the system bromotrifluoromethane/tris-(diethylamino)phosphane, while trichloro(trifluoromethyl)silane is prepared by nucleophilic trifluoromethylation of tetrachlorosilane with bromotrifluorornethane/tris(diethylamino)phos-phane. " ... 

Bis(diisopropylamino)phosphanyl(trimethylsilyl)diazomethane 6, easily available by treatment of chlorobis(diisopropylamino)phosphane with lithiated diazo(trimethylsilyl)methane, provides upon flash thermolysis at 250"C the so-called stable carbene 7.38,39,40 behaves partly as a nucleophilic carbene and reacts only with electron-deficient alkenes such as methyl propenoate or diethyl fumarate under cyclopropanation." In the former case only the Z-isomer 8 is formed. Cyclopropane 9 is thermally unstable and is, therefore, oxidized in situ at the phosphorus atom with elemental sulfur to provide cyclopropane 10, Cyclopropanes 8 and 9 are also generated from the diazo compound 6 and the appropriate alkene by photolysis." ... 

The efficiencies of DBU (1) and DBN (2) as sterically hindered (non-nucleophilic) and strong organobase catalysts have been widely demonstrated [5]. However, Reed et al. [12] claimed that they could behave as strong nucleophiles in the reaction of chlorobis (diisopropylamino)phosphane and DBU (1) or DBN (2). 

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See also in sourсe #XX -- [ , ]

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