TY - JOUR
T1 - "Naked" [Mn3O]7+ triangles
T2 - The effect of auxiliary ligands on magnetic exchange
AU - Manolopoulou, Efi
AU - Stoumpos, Constantinos C.
AU - Siczek, Milosz
AU - Lis, Tadeusz
AU - Brechin, Euan K.
AU - Milios, Constantinos J.
PY - 2010
Y1 - 2010
N2 - The reaction between Mn(ClO4)2-6H2O, Et-saoH2 (Et-saoH2 = 2-hydroxypropiophenone oxime), NEt4OH and [Ni(pao)2(py)2] (paoH = 2-pyridylaldoxime) in MeOH forms the complex [MnIII 3O(Et-sao)3(HCO2)(MeOH)5] (1) in good yields. The reaction of MnCl2-4H2O, Me-saoH 2 (Me-saoH2 = 2-hydroxyphenylethanone oxime), NEt 14OH and DL-valine in MeOH gives the complex [MnIII 3SO(Me-SaO)3(MeOH)5]Cl (2) in moderate yields. In both complexes the building block consists of a triangular {Mn III30(R-sao)3} unit (R = Et, Me for 1 and 2, respectively). In the case of 2, the [Mn3] unit can be considered "naked" as there is no capping ligand present, whereas in the case of 1 a formate ion is terminally bonded to one metal centre. DC magnetic susceptibility measurements for 1 and 2 reveal the presence of both ferromagnetic and antiferromagnetic intramolecular interactions, depending on the Mn-N-O-Mn torsion angles within each cluster, leading to a ground state S = 2 for both, complexes. Rationalization of this result is attempted by structural comparison of previously reported triangular [Mn3] oximate complexes on the basis of "flat" and "twisted" torsion angles and the effect of the auxiliary ligands.
AB - The reaction between Mn(ClO4)2-6H2O, Et-saoH2 (Et-saoH2 = 2-hydroxypropiophenone oxime), NEt4OH and [Ni(pao)2(py)2] (paoH = 2-pyridylaldoxime) in MeOH forms the complex [MnIII 3O(Et-sao)3(HCO2)(MeOH)5] (1) in good yields. The reaction of MnCl2-4H2O, Me-saoH 2 (Me-saoH2 = 2-hydroxyphenylethanone oxime), NEt 14OH and DL-valine in MeOH gives the complex [MnIII 3SO(Me-SaO)3(MeOH)5]Cl (2) in moderate yields. In both complexes the building block consists of a triangular {Mn III30(R-sao)3} unit (R = Et, Me for 1 and 2, respectively). In the case of 2, the [Mn3] unit can be considered "naked" as there is no capping ligand present, whereas in the case of 1 a formate ion is terminally bonded to one metal centre. DC magnetic susceptibility measurements for 1 and 2 reveal the presence of both ferromagnetic and antiferromagnetic intramolecular interactions, depending on the Mn-N-O-Mn torsion angles within each cluster, leading to a ground state S = 2 for both, complexes. Rationalization of this result is attempted by structural comparison of previously reported triangular [Mn3] oximate complexes on the basis of "flat" and "twisted" torsion angles and the effect of the auxiliary ligands.
KW - Ligand effects
KW - Magnetic properties
KW - Manganese
KW - Oximes
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U2 - 10.1002/ejic.200900905
DO - 10.1002/ejic.200900905
M3 - Article
AN - SCOPUS:74549207693
SN - 1434-1948
SP - 483
EP - 489
JO - European Journal of Inorganic Chemistry
JF - European Journal of Inorganic Chemistry
IS - 3
ER -