Hydrochloric Acid → Phosphine, cyclohexyldiphenyl-

Participants

Reaction Steps

154 ml of a 1.72 Molar titrated solution of 0.266 mole of cyclohexylmagnesium chloride in ether was added dropwise to a stirred solution of 47.54 g (0.2656 mole) of phenyldichlorophosphine in 400 ml of anhydrous ether, maintained at +10° C. under an inert atmosphere. After the addition was complete the mixture was stirred for 15 minutes at +10° C. A 2.0 Molar solution of 0.319 mole of phenylmagnesium bromide in 159 ml of ether was then added dropwise at a temperature of between +10° and +22° C. The mixture was warmed to reflux for one-half hour, then cooled to +6° C. and treated dropwise with 160 ml of water then 14 ml of concentrated hydrochloric acid. The mixture was made basic with 10 ml of concentrated ammonium hydroxide (to pH=9) and the ether phase was separated, dried with magnesium sulfate and concentrated to yield a yellow waxy solid. Recrystallization from ethanol gave cyclohexyldiphenylphosphine. MP=52.5°-57.5° C., 31P-NMR δ=-1.97 ppm (relative intensity 999.93) and δ=-1.25 ppm (dicyclohexylphenylphosphine impurity-relative intensity=13.25), Yield=about 70%.

Provenance & Evidence