Cleavage of the Indium(III) Octaethyloxophlorin Dimer, {InIII(OEPO)}2, with Lewis Bases. Importance of Outer-Sphere Hydrogen Bonding in Adduct Structures

• Published in: Inorganic chemistry Vol. 47; no. 23; pp. 11417 - 11422
• Main Authors: Garcia, Thelma Y, Olmstead, Marilyn M, Fettinger, James C, Balch, Alan L
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 01-12-2008
• Subjects: Crystallography, X-Ray; Electrons; Hydrogen Bonding; Ligands; Magnetic Resonance Spectroscopy; Organometallic Compounds - chemistry; Porphyrins - chemistry
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/ic801605b

Splitting of the oxygen-bridged dimer {InIII(OEPO)}2 [where (OEPO)3− is the trianion of octaethyloxophlorin] by potential axial ligands has been examined and compared to results obtained previously for the cleavage of {FeIII(OEPO)}2. Treatment of {InIII(OEPO)}2 with an excess of imidazole (im) produced the crystalline complex {(im)2InIII(OEPO···im)}2·(im)2InIII(OEPO)·2Cl2C6H4. This solid contains two different (im)2InIII(OEPO) units that are bridged through hydrogen bonding by an uncoordinated imidazole. Treatment of {InIII(OEPO)}2 with an excess of pyridine (py) produced (py)2InIII(OEPO), which is isostructural with (py)2FeIII(OEPO). Although {FeIII(OEPO)}2 reacted with xylyl isocyanide (xylylNC) to form the novel free-radical complex (2,6-xylylNC)2FeII(OEPO•) [where (OEPO•)2− is the radical dianion of octaethyloxophlorin], {InIII(OEPO)}2 was unreactive toward xylyl isocyanide.