The complex [Pd(azoMe)(κ 1 -dppm)(κ 2 -dppm)]TfO (azoMe = 2-(4‘-tolylazo)-5-methylphenyl, dppm = bis(diphenylphosphino)methane, TfO = CF 3 SO 3 ) reacts at room temperature with aryl azides N 3 Ar to give, in moderate to high yields, iminophosphorane complexes [Pd(κ 2 -azoMe- C, N ‘){κ 2 -PPh 2 CH 2 P( NAr)Ph 2 - P, N }]TfO [Ar = C 6 H 4 R, R = H ( 1 ), MeO-2 ( 2a ), Me-2 ( 2b ), NO 2 -2 ( 2c ), MeO-3 ( 3a ), NO 2 -3 ( 3c ), MeO-4 ( 4a ), Me-4 ( 4b ), NO 2 -4 ( 4c )]. In all cases, there is a linear correlation between δ(P) (ppm) of both phosphorus atoms and temperature T (°C) [δ(P 1 ) = δ 1 (0) + a 1 T; δ(P 2 ) = δ 2 (0) + a 2 T ]. 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, | a 1 |, | a 2 | = (0−12) × 10 - 3 ppm/°C. In the other complexes, the gradient of one of the straight lines is positive ( a 1 ≈ 26 × 10 - 3 ppm/°C) and that of the other is negative ( a 2 ≈ −7.5 × 10 - 3 ppm/°C). Both lines cross in the range 0−25 °C. 4b reacts with [Au(acac)PPh 3 ] (1:2) to give [Pd(azoMe-C,N‘){PPh 2 C(AuPPh 3 ) 2 P( NAr)Ph 2 - P, N }] [Ar = Me-4 ( 5b )]. [Pd(azoMe- C, N ‘)(κ 2 -dppm)]TfO reacts with NaN 3 to give [Pd 2 (azoMe) 2 (μ 2 -N 3 )(μ 2 -dppm) 2 ]TfO ( 6 ). The crystal structure of 4b is reported.
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Vicente et al. (1998) studied this question.