New rhodium complexes of the tetradentate ligand bis(diacetylmonoxime-imino)propane 1,3 (H2dopn): synthesis and crystal structure of trans-[Rh(Hdopn)Cl]2 and trans-[Rh(Hdopn)(I)2]

The reaction between [Rh(H2O)6](ClO4)3 and the monoanion Hdopn− (H2dopn=bis(diacetylmonoxime-imino)propane 1,3=3,9-dimethyl-4,8-diazaundeca-3,8-diene-2,10-dione dioxime) afforded a new dimeric rhodium(II) compound of formula [Rh(Hdopn)(H2O)]2(ClO4)2 · H2O (1). Treatment of methanolic solution of 1 with NaX (X=Cl−, Br−, I−) results in the replacement of water with halides in 1, leading to the formation of [Rh(Hdopn)X]2 rhodium(II) dimers. The X-ray crystal structure of [Rh(Hdopn)Cl]2 · 0.5H2O (2) was determined showing a [Rh(II)–Rh(II)] core. Upon the reaction of 1 with NaI carried out in air, [Rh(Hdopn)(I)2] (3) was isolated and characterized by a single-crystal X-ray diffraction analysis.