Metal Ion Binding to Octakis(dimethylamino)porphyrazine: Core Coordination of Mn(III) and Peripheral Coordination of Pd(II)

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• 作者：David P. Goldberg ; Antonio Garrido Montalban ; Andrew J. P. White ; David J. Williams ; Anthony G. M. Barrett ; and Brian M. Hoffman
• 刊名：Inorganic Chemistry
• 出版年：1998
• 出版时间：June 15, 1998
• 年：1998
• 卷：37
• 期：12
• 页码：2873 - 2879
• 全文大小：145K
• 年卷期：v.37,no.12(June 15, 1998)
• ISSN：1520-510X

文摘

The synthesis and X-ray structural characterization oftwo manganese(III) porphyrazine (tetraazaporphyrin)complexes are reported:[Mn(Et₂dtc)ODMAPz] (1) and[Mn(Cl)ODMAPz] (2) (Et₂dtc =diethyldithiocarbamato;ODMAPz =2,3,7,8,12,13,17,18-octakis(dimethylamino)porphyrazinato).In both 1 and 2, the Mn(III) ionsits~0.3 Å out of the plane of the pyrrolic nitrogen atoms toward theaxial ligand. The structural data reveal thatfor both 1 and 2 the Mn(III) ions areisolated from each other, simplifying the interpretation of themagneticbehavior of these compounds. Cyclic voltammetry shows that theperipheral dimethylamino groups make thesemetalloporphyrazines extremely electron-rich, with theMn(III)/Mn(II) couple at -1.3 V (versusferrocenium/ferrocene), shifted approximately 0.6-0.9 V more negative than thoseof related manganese macrocycles.Temperature-dependent magnetic susceptibility measurements showthat the ground state is S = 2 with axialzero-field splitting, and D = 3.1-3.3cm^-1 for both 1 and 2.These bulk magnetic measurements are comparedto the magnetic behavior of Mn(III) porphyrin-type complexes, aswell as recent direct resonance measurementson 1 and 2 by high-field EPR spectroscopy.The related metalloporphyrazine NiODMAPz, with aninternallybound Ni(II) ion, coordinates 4 equiv of PdCl₂ to theperipheral dimethylamino sites to give[Ni(ODMAPz)(PdCl₂)₄] (5). Compound1 crystallizes in C2/c, with a= 22.480(3) Å, b = 20.128(2) Å,c = 19.423(3) Å, =102.97(1), V = 8564(2) ų, andZ = 8 (R₁ = 0.074,wR₂ = 0.169). Compound 2crystallizes in P with a =10.216(6) Å, b = 13.426(8) Å, c =15.683(14) Å, = 114.59(5), =96.82(6), = 101.87(5), V =1863(2)ų, and Z = 2 (R₁ =0.067, wR₂ = 0.183).