Chlorodiphenylphosphine

Chlorodiphenylphosphine is an organophosphorus compound with the formula (C6H5)2PCl, abbreviated Ph2PCl. It is a colourless oily liquid with a pungent odor that is often described as being garlic-like and detectable even in the ppb range. It is useful reagent for introducing the Ph2P group into molecules, which includes many ligands. Like other halophosphines, Ph2PCl is reactive with many nucleophiles such as water and easily oxidized even by air.(ppm vs 85% H3PO4) Chlorodiphenylphosphine is an organophosphorus compound with the formula (C6H5)2PCl, abbreviated Ph2PCl. It is a colourless oily liquid with a pungent odor that is often described as being garlic-like and detectable even in the ppb range. It is useful reagent for introducing the Ph2P group into molecules, which includes many ligands. Like other halophosphines, Ph2PCl is reactive with many nucleophiles such as water and easily oxidized even by air. Chlorodiphenylphosphine is produced on a commercial scale from benzene and phosphorus trichloride (PCl3). Benzene reacts with phosphorus trichloride at extreme temperatures around 600 °C to give dichlorophenylphosphine (PhPCl2) and HCl. Redistribution of PhPCl2 in the gas phase at high temperatures results in chlorodiphenylphosphine. Alternatively such compounds are prepared by redistribution reactions starting with triphenylphosphine and phosphorus trichloride. Synthesis of Ph2PCl by the direct reaction of phenylmagnesium bromide and phosphorus trichloride is not practiced. On the other hand, PCl3 can be usefully converted to an aminophosphine, which in turn undergoes alkylation or arylation: Subsequent cleavage of the P-N bond with HCl gives the chlorophosphine: Unlike the synthesis of chlorodiisopropylphosphine, reaction of two equivalents of the phenyl Grignard reagents with PCl3 does not efficiently afford the monochloride. Chlorodiphenylphosphine hydrolyzes to give diphenylphosphine oxide. Chlorodiphenylphosphine, along with other chlorophosphines, is used in the synthesis of various phosphines. A typical route uses Grignard reagents: The phosphines produced from reactions with Ph2PCl are further developed and used as pesticides (such as EPN), stabilizers for plastics (Sandostab P-EPQ), various halogen compound catalysts, flame retardants (cyclic phosphinocarboxylic anhydride), as well as UV-hardening paint systems (used in dental materials) making Ph2PCl an important intermediate in the industrial world. Chlorodiphenylphosphine is used in the synthesis of sodium diphenylphosphide via its reaction with sodium metal in refluxing dioxane.