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A novel redox reaction involving fluoride and phosphine complexes of palladium(I1) is reported. The scope of this reaction has been investigated using the ligands PPh3, Ph2P(CH2),PPh2 (n = 1-4), Ph2PCH,C(CH3),CH2PPh2, Ph2PCHS, and P(CH2CH,CN),; several solvents including DMSO, pyridine, acetonitrile, and THF; and either n-BuJF.3H20 or KF/ 18-crown-6 as the fluoride source. The reduction groducts are palladium(0) phosphine complexes for which this reaction offera a convenient synthetic route. 'P and lgF NMR spectra permitted identification of the initial oxidation products as difluorophosphoranes (R3PF2), which subsequently hydrolyzed, forming phosphine oxides if a hydrated fluoride source is used. Results implicating a fluoride-induced redox reaction in the thermal decomposition ofare also presented. Preliminary results indicate that platinum complexes also undergo this reaction, but nickel complexes yield NiF2. The X-ray parameters for Pd(dppp), dppp 13.290 (1) a c = 20.186 (2) 1, B = 109.383 (5)O, and 2 = 4. = 1,3-bis(di henyphosphino) ropane) are: monoclinic, space group C2/c (No. 15), a = 18.396 (2) s , b =

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The preparation and characterization of nine compounds of the type (00 20 2)3 are reported. Compound 1 (Y = lone pair) is unstable but forms the stable derivatives 2-9 (Y = O, S, Se, H+(BF4~), Ph3C+(BF4_), H3B, (OC)sW, and (OC)5Mo, respectively) upon reaction in situ with appropriate substrates. NMR parameters (31P, , and l3C) are consistent with a tricyclic structure for 5 and 6 which contains a transannular P-<-N bond. Such spectra are also consistent with a bicyclic structure for 2-4, 7, 8, and 9 in which phosphorus has a tetrahedral and nitrogen a nearly trigonal planar coordination geometry. Recently obtained crystallographic x-ray data for 3, 5, and 7 are confirmatory of these conclusions. Apparently groups such as Fl+ and Ph3C+, which strongly polarize the phosphorus lone pair, also cause the nitrogen lone pair to engage in transannular P«-N bond formation. This bond accounts for the unusual stability of the P-H link in 5 even in strongly basic media. The nitrogen in compounds 2-4, 8, and 9 can be quaternized with a methyl group to form the corresponding cations 12-14,10, and 11, respectively. In these products the -H steric interactions which favor a planar nitrogen in the reactants are overcome to some extent, causing some puckering of the nitrogen atom toward a tetrahedral configuration.