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The molecular adduct (CH3)2OPF5 is shown to rearrange slowly at room temperature according to the equation 3(CH3)2OPF5 -2(CH3)30+PF6-+ POF3. The reaction of (CH3)2SPF5 was also studied and found to be dissimilar to the ether system in that two solid salts were formed along with gaseous PF3; viz., 3(CH3)2SPF3 (CH3)3S+PF6_ + (CH3)2SSCH3+PF6~+ PF3. These reactions are surprising in that they have no analogy in any previously studied systems of boron or fluorophosphorane adducts with Lewis bases. Characterization of the stable solid salts by infrared and proton nmr is reported.

The compounds CH3PF3H and C2H5PF3H have been prepared by the reaction of the respective alkyltetrafluorophosphorane with trimethyltin hydride. These compounds are considerably more stable than HPF4 and H2PF3 and may be manipulated and stored in Pyrex apparatus without decomposition. Infrared spectra and 1H and 19F nmr spectra at low temperatures confirm an equatorial-substituted trigonal-bipyramidal geometry for both alkylhydridofluorophosphoranes. At room temperature the nmr spectra indicate a substantial averaging of axial and equatorial fluorine atom environments owing to intramolecular exchange processes.Ivanova and Kirsanov reported in 1961 the synthesis of three arylhydridotrifluorophosphoranes, ArPFsH (Ar = j>-chlorophenyl, ^-tolyl, and phenyl), by the oxidative reaction of KHF2 with the respective aryldichlorophosphine.2 The same reaction with alkyldichlorophosphines is reported in a patent3 to yield alkylhydridotrifluorophosphoranes in situ. These products were not characterized, however, but were allowed to react with secondary amines giving a series of compounds of the general formula RPF2(NR'2)H (R = CHS, C2H5; R' = CH3, C2Hs, m-C4H9). We wish now to report the synthesis and characterization of CH3PF3H and C2HsPF3H as relatively stable entities from the exchange reactions of CH3PF4 and C2H5PF4, respectively, with (CH3)3SnH. These reactions are analogous to the reaction which we have recently reported for the preparation of HPF4 and H2PF3.4 Evidence is also presented for the formation of (CH3)2NPF3H from the exchange reaction between (CH3)2NPF4 and (CH3)3SnH. This compound could not be obtained in pure form, however.

Alkyltetrafluorophosphoranes can be prepared in good yield by the room temperature reaction of phosphorus pentafluoride and tetraalkyltin compounds. Careful investigation of the stoichiometry of this reaction indicates that this reaction is not as straightforward as one might expect, however. In all of the reactions attempted some of the phosphorus was retained in the nonvolatile residue of the reaction. Evidence is presented which indicates that this residue contains a complex of the formula R3SnPF6, whose structure is probably similar to other known compounds RsSnX (X = CIO,•, BF4, AsFe, and SbF6).Alkyltetrafluorophosphoranes have been synthesized by a number of different methods. The method de-Contribution from the

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