Self-assembled Transition Metal Coordination Frameworks of ...

__ g_ _g g H g __ Manganese(II) complexes
compounds of manganese with thiocarbohydrazones or with carbohydrazones.
However, a very closely related Mn(II) tetranuclear complex, [Mn(2-OHpicpn)]4'
(ClO4)4, is reported [20] with its catalytic disproportionation of hydrogen peroxide,
showing the possibility of formation of Mn(Il) squares. Also, there are reports of
mono and binuclear carbohydrazide Mn(ll) complexes as energetic materials [21-24].
Coordination number and configuration of [Mn(carbohydrazide)3](C104); are six and
octahedron respectively, and for the other three binuclear complexes of Mn(II) are
seven and pentagonal bipyramid configuration [21]. Simultaneously, the first example
of a seven-coordinate Mn(II) complex with a monodentate organic ligand N,N’dimethylurea
have been reported [25]. The Mn(lI) complex of bis(2­
hydroxyacetophenone) thiocarbohydrazone and that of bis(5-chlorosalicylaldehyde)
thiocarbohydrazone are assigned to mononuclear with octahedral geometry [26]. The
aim of the present work is the synthesis and characterization of novel coordination
frameworks of magnetically coupled Mn(lI) complexes.
5.2. Experimental
5.2.1. Materials
MnCl2- 4H2O (Fluka), Mn(CH3COO)2- 4H2O (Merck), Mn(ClO4)2- 6H2O
(Aldrich), NaN3 (Reidel-De Haen), HCIO4, HCl, etc were used as received and
solvents were purified by standard procedures before use.
Caution! Perchlorate and azide complexes of metals with organic ligands are
potentially explosive and should be handled with care.
5.2.2. Synthesis of Mn (II) complexes
[Mn;_(HL2)L2];Cl;- CHCl3- 9H;0 (19)
A solution of MnCl2~ 4H2O (0.199 g, l mmol) in l0 ml of methanol was
added to a solution of H2L2 (0.440 g, l mmol) in 10 ml chloroform and refluxed for 1
h and allowed to stand at room temperature. Orange colored product separated out
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