HCl + Ph 3P → Cl + 4HCl + Ph 3PO Protonation. Bis(triphenylphosphine)iminium chloride (PPN +Cl −, formula Cl is prepared from triphenylphosphine dichloride: 2 Ph 3PCl 2 + NH 2OH This reagent is used to convert alcohols to alkyl chlorides in organic synthesis. PPh 3 + RN 3 + H 2O → OPPh 3 + N 2 + RNH 2 Chlorination Ĭl 2 adds to PPh 3 to give triphenylphosphine dichloride (Cl), which exists as the moisture-sensitive phosphonium halide. Typically the intermediate phosphanimine is not isolated. The phosphanimine can be hydrolyzed to the amine. Illustrative is the preparation of triphenylphosphine phenylimide: Īryl azides react with PPh 3 to give phosphanimines, analogues of OPPh 3, via the Staudinger reaction. PPh 3 can also form an adduct with Te, although this adduct primarily exists as (Ph 3P) 2Te rather than PPh 3Te. Salts of selenocyanate, SeCN −, are used as the Se 0 source. Triphenylphosphine selenide, Ph 3PSe, may be easily prepared via treatment of PPh 3 with red (alpha-monoclinic) Se. This reaction can be employed to assay the "labile" S 0 content of a sample, say vulcanized rubber. The phosphorus-containing product is triphenylphosphine sulfide, Ph 3PS. Simple organosulfur compounds such as thiols and thioethers are unreactive, however. Triphenylphosphine abstracts sulfur from polysulfide compounds, episulfides, and elemental sulfur. This method capitalizes on the fact that OPPh 3 is more polar and hence more soluble in polar solvents than PPh 3. This impurity can be removed by recrystallisation of PPh 3 from either hot ethanol or hot isopropanol. Triphenylphosphine undergoes slow oxidation by air to give triphenylphosphine oxide, Ph 3PO: Principal reactions with chalcogens, halogens, and acids Oxidation 
Triphenylphosphine crystallizes in triclinic and monoclinic modification In both cases, the molecule adopts a pyramidal structure with propeller-like arrangement of the three phenyl groups. The industrial synthesis involves the reaction between phosphorus trichloride, chlorobenzene, and sodium.: PCl 3 + 3 PhCl + 6 Na → PPh 3 + 6 NaCl
Triphenylphosphine can be prepared in the laboratory by treatment of phosphorus trichloride with phenylmagnesium bromide or phenyllithium. 2 Principal reactions with chalcogens, halogens, and acids.
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