1.A study of the IR spectra of bis(2,2,2-trichloro-1,1-dimethylethyl) hydrogen phosphite and of bis[2-chloro-1-(chloromethyl)ethyl] hydrogen phosphite indicates that these substances contain quinquvalent phosphorus.2.2,2,2-Trichloro-1,1-dimethylethyl dihydrogen phosphite was synthesized, and its IR spectrum was determined.3.Bis[2,2,2-trichloro-1-(trichloromethyl)ethyl] phosphorochloridite and bis[2,2-dichloro-1-(dichlo-romethyl) ethyl]phosphorochloridite were synthesized by the action of phosphorus trichloride on 1,1,1,3,3,3-hexachloro-2-propanol and 1,1,2,2-tetrachloro-2-propanol, respectively.