Abstract
Synthesis of phenylditolylphosphine by means of the Friedel-Crafts reaction was investigated, and the isomer ratio of the product was determined. Phenylphosphonous dichloride reacted with a large excess of toluene in an autoclave at 210220°C in the presence of aluminum trichloride, giving phenylditolylphosphine (1).
On the other hand, ditolylphosphinous chloride-aluminum trichloride complex (2), which was obtained by the reaction between toluene and phosphorus trichloride in the presence of aluminum trichloride, was converted to ethyl ditolylphosphinite (3) by treatment with ethanol and triethylamine. Another crop of phenylditolylphosphine (1′) was obtained from the phosphinite by treatment with phenylmagnesium bromide.
These phoshines were mixtures of isomeric phenylditolylphosphines having two tolyl groups at ortho, meta, and/or para positions. In this study, the ratios of the isomers were also analyzed by comparing their liquid-gas chromatograms and infrared spectra with those of authentic samples.
