Palladium(II) Complexes of Monoaryliminophosphorane Derivatives of 1,2-Bis(Diphenylphosphino)methane. Crystal Structure of [Pd{κ²-C₆H₃(NN−C₆H₄Me-4‘)-2- (C₆H₄Me-4‘‘)-5-<i>C</i>,<i>N</i>‘}{κ²-PPh₂CH₂P(NC₆H₄Me-4)Ph₂-<i>P</i>,<i>N</i>}]^†

The complex [Pd(azoMe)(κ1-dppm)(κ2-dppm)]TfO (azoMe = 2-(4‘-tolylazo)-5-methylphenyl, dppm = bis(diphenylphosphino)methane, TfO = CF3SO3) reacts at room temperature with aryl azides N3Ar to give, in moderate to high yields, iminophosphorane complexes [Pd(κ2-azoMe-C,N‘){κ2-PPh2CH2P(NAr)Ph2-P,N}]TfO [Ar = C6H4R, R = H (1), MeO-2 (2a), Me-2 (2b), NO2-2 (2c), MeO-3 (3a), NO2-3 (3c), MeO-4 (4a), Me-4 (4b), NO2-4 (4c)]. In all cases, there is a linear correlation between δ(P) (ppm) of both phosphorus atoms and temperature T (°C) [δ(P1) = δ1(0) + a1T; δ(P2) = δ2(0) + a2T]. In the ortho-substituted complexes 2a−c and the nitro derivatives 3c and 4c, crossing of the two δ/T plots of each complex is not observed and the change in chemical shift with temperature is small or nil, |a1|, |a2| = (0−12) × 10-3 ppm/°C. In the other complexes, the gradient of one of the straight lines is positive (a1 ≈ 26 × 10-3 ppm/°C) and that of the other is negative (a2 ≈ −7.5 × 10-3 ppm/°C). Both lines cross in the range 0−25 °C. 4b reacts with [Au(acac)PPh3] (1:2) to give [Pd(azoMe-C,N‘){PPh2C(AuPPh3)2P(NAr)Ph2-P,N}] [Ar = Me-4 (5b)]. [Pd(azoMe-C,N‘)(κ2-dppm)]TfO reacts with NaN3 to give [Pd2(azoMe)2(μ2-N3)(μ2-dppm)2]TfO (6). The crystal structure of 4b is reported.