Abstract: | The reaction of C5H5Rh(CO)(PiPr3) (1] which is prepared from C5H5Rh(CO)2 and neat P1Pr3, with the nitriloxides 2-RC6H4CNO (R = H, Cl) leads to the formation of the metallaheterocycles C5H5(P1Pr3)
) (2, 3) in 90–95% yield. Compound 1 reacts with tosylazide to give the C,N-bound isocyanate complex C5 H5(PiPr3)Rh(η2-TosN=C=O) (6). Analogously, on treatment of C5Me5Co(CO)(PMe3) with phenylazide the phenylisocyanate derivative C5Me5(PMe3)Co(η2-PhN=C=O) (7) is formed. Protonation of 7 with CF3CO 2H affords the non-ionic carbamoylcobalt complex C5Me5(PMe3)CoC(O)NHPh](O2CCF3) (8). The X-ray structural analysis of 2 reveals the presence of an almost planar
heterocycle in which the two Rh-C distances differ by 0.045 Å |