Synthesis of the tris-cyclometalated complex fac-[Rh(ptpy)3] and X-ray crystal structure of [Rh(acac)(ptpy)2]

New convenient syntheses of the cyclometalated complexes [Rh(acac)(ptpy)2] (3, ptpy = 2-(p-tolyl)pyridinato) and fac-[Rh(ptpy)3] (4) are described. The compounds were prepared in a kind of one-pot synthesis starting from in situ prepared [Rh(acac)(coe)2] (2) (coe = cis-cyclooctene) followed by reaction with Hptpy in refluxing toluene. Under these conditions oxidative addition occurred and the new complex 3 was obtained in good yields. Compound 4 was prepared in good yields by reaction of 3 with Hptpy in excess. The complex 3 crystallized from dichloromethane/iso-hexane in the space group P − 1 and its molecular structure was confirmed by a single-crystal X-ray diffraction study. The absorption and emission spectra exhibit the new compounds as red-emitting phosphorescent complexes.