Determining the Electronic Structure of a Series of [(phen)3M]0 (M = Ti, V, Mo) and [(pdi)2M]n+ (M = Cr, Mo) Complexes: Coordination of Neutral Ligands vs. π‐Radical Anions. Issue 20 (22nd June 2015)

• Record Type: Journal Article
• Authors: Wang, Mei; Weyhermüller, Thomas; Wieghardt, Karl
• Is Part Of: European journal of inorganic chemistry. Issue 20(2015)
• Page Start: 3246
• Page End: 3254
• Publication Date: 2015-06-22
• Subjects: Electronic structure -- Radical ions -- Ligand effects -- N ligands -- Molybdenum; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201500420
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: The molecular and electronic structures of newly synthesized complexes containing 2, 6‐bis[1‐(4‐methoxyphenylimino)ethyl]pyridine (pdi) ligands have been determined by high‐resolution X‐ray crystallography, electronic and electron‐spin resonance spectroscopy, and temperature‐dependent magnetic susceptibility measurements: [Mo IV (pdi ·· )(pdi 2– )] 0 ( S = 0)1, [Mo IV (pdi 2– )(pdi · )](BF4 ) ( S = 1/2)2, [Cr III (pdi ·· )(pdi · )] 0 ( S = 0)3, [Cr III (pdi · )(pdi 0 )](BF4 )2 ( S = 1)4, [M III ( Me phen · )3 ] 0 (M = Cr5, Mo6, Ti7, and V8 ). Complexes5 –8 contain π‐radical anions of 2, 9‐dimethyl‐1, 10‐phenanthroline. Monoanionic radicals ( S L = 1/2) are designated (pdi · ) 1– and ( Me phen · ) 1–, whereas their neutral analogues are (pdi 0 ) and ( Me phen 0 ) and the dianions are (pdi ·· ) 2– ( S L = 1) and (pdi 2– ) 2– ( S L = 0). We show here that the oxidation level of these ligands can be determined experimentally in complexes1 –8 by high‐quality single‐crystal X‐ray crystallography at low temperature (ca. 100 K). Abstract : The appropriate oxidation levels of the tridentate ligands pyridine‐2, 6‐diimine (pdi) and 2, 9‐dimethyl‐1, 10‐phenanthroline ( Me phen) as neutral species, monoanion π‐radical and dianion in "low valent" octahedral complexes [M( Me phen)3 ] 0 (M = Ti, V, Cr, Mo) and [Mo(pdi)2 ] n ( n = 0, 1+) have been experimentally determined by X‐ray crystallography and by UV/Vis and EPR spectroscopy.