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-C,N′}{κ2-PPh2CH2P(=NC6H4Me-4)Ph2-P,N}]

The complex [Pd(azoMe)(kappa(1)-dppm)(kappa(2)-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(kappa(2-)azoMe-C,N'){kappa(2)-PPh2CH2P(=NAr)Ph-2-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 delta(P) (ppm) of both phosphorus atoms and temperature T (degrees C) [delta(P-1) = delta(1)(0) + a(1)T; delta(P-2) = delta(2)(0) + a(2)T]. In the ortho-substituted complexes 2a-c and the nitro derivatives 3c and 4c, crossing of the two delta/T plots of each complex is not observed and the change in chemical shift with temperature is small or nil, /a(1)/, /a(2)/ = (0-12) x 10(-3) ppm/degrees C. In the other complexes, the gradient of one of the straight; lines is positive (a(1) approximate to 26 x 10(-3) ppm/degrees C) and that of the other is negative (a(2) approximate to -7.5 x 10(-3) ppm/degrees C). Both lines cross in the range 0-25 degrees C. 4b reacts with [Au(acac)PPh3] (1:2) to give [Pd(azoMe-C,N'){PPh2C(AuPPh3)(2)P(=NAr)Ph-2-P,N}] [Ar = Me-4 (5b)]. [Pd(azoMe-C,N')(kappa(2)-dppm)]TfO reacts with NaN3 to give [Pd-2(azoMe)2(C)(mu(2)-N-3)(mu(2)-dppm)(2)]TfO (6). The crystal structure of 4b is reported.