Synthesis, structures, and EPR-spectra of the rhenium(II) nitrosyl complexes [Re(NO)Cl2(PPh3)(OPPh3)(OReO3)], [Re(NO)Cl2(OPPh3)2(OReO3)], and [Re(NO)Cl2(OPPh3)3](ReO4)

The paramagnetic rhenium(II) nitrosyl, complexes [Re(NO)Cl-2(PPh3)(OPPh3)(OReO3)], [Re(NO)Cl-2(OPPh3)(2).(OReO3)], and [Re(NO)Cl-2(OPPh3)(3)](ReO4) are formed during the reaction of [ReOCl3(PPh3)(2)] with NO gas in CH2Cl2/EtOH. These and two other Re-II complexes with 5d(5) "low-spin"-configuration can be observed during the reaction EPR spectroscopically. Crystal structure analysis shows linear coordinated NO ligands (Re-N-O-angles between 171.9 and 177.3 degrees). Three OPPh3 ligands are meridionally coordinated in the final product of the reaction, [Re(NO)Cl-2(OPPh3)(3)][ReO4] (monoclinic, P2(1)/c, a = 13.47(1), b = 17.56(1), c = 24.69(2) Angstrom, beta = 95.12(4)degrees, Z = 4). [Re(NO)Cl-2(PPh3)(OPPh3)(OReO3)] (triclinic <P(1)over bar>, a = 10.561(6), b = 11.770(4), c = 18.483(8) Angstrom, alpha = 77.29(3), beta = 73.53(3), gamma = 64.70(4)degrees, Z = 2) and [Re(NO)Cl-2(OPPh3)(2)(OReO3)] (monoclinic P2(1)/c, a = 10.652(1), b = 31.638(4), c = 11.886(1) Angstrom, beta = 115.59(1)degrees), Z = 4) can be isolated at shorter reaction times besides the complexes [Re(NO)Cl-3(Ph3P)(2)], [Re(NO)Cl-3(Ph3P).(Ph3PO)], and [ReCl4(Ph3P)(2)].