Prepd by adding dropwise a mixture of dimethylaniline and benzyl alc to a soln of phosphorus trichloride in benzene: F. R. Atherton et al., J. Chem. Soc. 1945, 382; US 2490573 (1949 to Hoffmann-La Roche). 1H, 13C, 31P NMR data: J. Perruchon et al., Synthesis 2007, 3553.