Preparation and characterization of different two types of di-μ-oxo dimanganese(IV) complexes with tetradentate Schiff bases

Comparison of two MnIVMnIV-bis-μ-oxo complexes {[MnIV(N4(6-Me-DPEN))]2(μ-O)2}2+ and {[MnIV(N4(6-Me-DPPN))]2(μ-O)2}2+

“…The Mn1-Mn1 0 distances of 2.6899 (15) Å in 1 and 2.6825 (7) Å in 2 are comparable to other literature examples (Krewald et al, 2013;Mullins & Pecoraro, 2008;Torayama, et al, 1998). The Mn-O bond lengths of 1.829 (3) and 1.835 (2) Å for 1 and 1.8350 (15) and 1.8325 (15) Å for 2 are also similar to literature reported values for Mn IV Mn IV (-O) 2 dimers (Krewald et al, 2013;Mullins & Pecoraro, 2008;Torayama et al, 1998). The octahedral geometry of the Mn centers of both structures are very similar in terms of bond angles, all of which are close to the ideal 90 and 180 .…”

“…As is true for all diamond cores, the O1-Mn1-O1 0 angle is slightly compressed at 85.53 (12) . Metrical parameters, Mn1-O1 = 1.829 (3) Å and Mn1-O1 0 = 1.835 (3) Å (Table 1) fall within the reported range (1.8 to 1.9 Å ) for oxo-bridged Mn IV complexes (Krewald et al, 2013;Mullins & Pecoraro, 2008;Torayama et al, 1998). The pyridine nitrogen atoms are outside the typical bonding range, but are oriented towards the Mn ion at distances of Mn1-N1= 2.348 (3) Å and Mn1-N4 = 2.368 (3) Å .…”

Magnetic assemblies based on Mn(III) salen analogues

“…Among such dinuclear complexes, the most attractive targets were di--oxo bridged Mn(IV) complexes. Since the first report in 1991 [42] [42][43][44][45][46][47]. The other has a structure in which each salen ligand acts as a bridging ligand to bind two Mn(IV) ions as well as the di--oxo-bridge, producing a formula [Mn 2 IV (-dbsalen) 2 (-O) 2 ] (Fig.…”

“…The other has a structure in which each salen ligand acts as a bridging ligand to bind two Mn(IV) ions as well as the di--oxo-bridge, producing a formula [Mn 2 IV (-dbsalen) 2 (-O) 2 ] (Fig. 4b) [46][47][48][49][50]. The Mn(IV) ions via the di--oxo bridge (including non-Schiff-base complexes) are strongly antiferromagnetically coupled with an exchange coupling in the range of −80 to −190 cm −1 (−110 to −270 K).…”

Synthesis, spectroscopy and redox properties of mononuclear manganese(II) and manganese(IV) complexes with N-(aryl)-pyridine-2-aldimine (L) and its amide derivatives. X-ray structural characterization of [Mn(MeL)2(NCS)2] (MeL = N-(4-methylphenyl)-pyridine-2-aldimine)

“…It has been established that oxygen and nitrogen from amino acid residues dominate the manganese coordination environment [11][12][13]. The importance of manganese in a number of biological systems [14][15][16][17][18] has stimulated the study of the chemistry of manganese(II), manganese(III), manganese(IV) and manganese(V) with variable nuclearity. The studies of the high oxidation state complexes of manganese are especially important because of their potential uses as oxidizing agents, catalysts [19][20][21] and electro catalysts [22][23][24] for the oxidation of compounds such as alcohols, esters and water [25,26].…”