Organophosphorus compounds. XVI. 2-(N-Dialkylamino)alkyldiphenylphosphines, phosphine oxides and sulphides as analogues of methadone

A series of 2-(N-dialkylamino)ethyldiphenylphosphine oxides and sulphides was prepared by the addition of a secondary amine to diphenylvinylphosphine oxide, or the phosphine sulphide, respectively. Similarly, a series of 2-(N-dialkylamino)propyldiphenylphosphine oxides was prepared from diphenylprop-1-enylphosphine oxide, or from diphenylprop-2-enylphosphine oxide which isomerized under the reaction conditions. Reduction of the 2-(N-dialkylamino)propyldiphenylphosphine oxides with trichlorosilane, and oxidation of the phosphines with sulphur, afforded the corresponding phosphine sulphides. None of the compounds showed significant analgesic activity.