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Abstract: A new convenient high-yield synthesis of the tris-cyclometalated complexes fac-[Rh(ppy)3] (4; ppy=2-phenylpyridinato) was developed. Complex 4 was prepared in a kind of one-pot synthesis starting from in situ prepared [Rh(acac)(coe)2] (2) which was heated in refluxing 2-phenylpyridine for a short time. After purification by filtration over alumina, compound 4 was obtained in yields of 65%. Also [Rh(acac)(ppy)2] (3) was prepared in a similar manner by oxidative addition of Hppy in refluxing toluene in high yields. In contrast to previous findings with the analogous iridium compounds, there was not any hint at the formation of the isomer mer-[Rh(ppy)3] using similar reaction conditions as applied for iridium. Furthermore the compound [{Rh(μ-Cl)(ppy)2}2] (5) was prepared from [{Rh(μ-Cl)(coe)2}2] (1) and Hppy in refluxing toluene in nearly quantitative yield. [Copyright &y& Elsevier]

Abstract: A convenient synthesis of the cyclometalated complex [{Rh(μ-Cl)(ptpy)2}2] (2, ptpy=2-(p-tolyl)pyridinato) is described. Compound 2 was obtained by oxidative addition of Hptpy towards [{Rh(μ-Cl)(coe)2}2] 1 (coe= cis-cyclooctene) in refluxing toluene in good yield. The complex 2 crystallized from chloroform/iso-hexane in the space group P21/n as solvate 2*2 CHCl3 and its molecular structure was confirmed by a single-crystal X-ray diffraction study. The emission spectrum exhibits the new compound as green-emitting phosphorescent complex. [Copyright &y& Elsevier]

Abstract: 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. [Copyright &y& Elsevier]