Cluster-based networks: 1D and 2D coordination polymers based on {MnFe2(μ3-O)}-type clusters.

A straightforward approach to heterometallic Mn-Fe cluster-based coordination polymers is presented. By employing a mixed-valent μ(3)-oxo trinuclear manganese(II/III) pivalate cluster, isolated as [Mn(II)Mn(III)(2)O(O(2)CCMe(3))(6)(hmta)(3)]·(solvent) (hmta = hexamethylenetetramine; solvent = n-propanol (1), toluene (2)) in the reaction with a μ(3)-oxo trinuclear iron(III) pivalate cluster compound, [Fe(3)O(O(2)CCMe(3))(6)(H(2)O)(3)]O(2)CCMe(3)·2Me(3)CCO(2)H, three new heterometallic {Mn(II)Fe(III)(2)} cluster-based coordination polymers were obtained: the one-dimensional polymer chain compounds {[MnFe(2)O(O(2)CCMe(3))(6)(hmta)(2)]·0.5MeCN}(n) (3) and {[MnFe(2)O(O(2)CCMe(3))(6)(hmta)(2)]·Me(3)CCO(2)H·(n-hexane)}(n) (4) and the two-dimensional layer compound {[MnFe(2)O(O(2)CCMe(3))(6)(hmta)(1.

One-dimensional coordination polymers from hexanuclear manganese carboxylate clusters featuring a {Mn(II)4Mn(III)2(mu4-O)2} core and spacer linkers.

The bridging of hexanuclear mixed-valent carboxylate coordination clusters of the type [Mn(6)O(2)(O(2)CR)(10)] (R = CMe(3); CHMe(2)) featuring a {Mn(II)(4)Mn(III)(2)(mu(4)-O)(2)} core by geometrically rigid as well as flexible spacer ligands such as pyrazine (pyz), nicotinamide (na), or 1,2-bis(4-pyridyl)ethane (bpe) results exclusively in one-dimensional (1D) coordination polymers. The formation of {[Mn(6)O(2)(O(2)CCMe(3))(10)(Me(3)CCO(2)H)(EtOH)(na)] x EtOH x H(2)O}(n) (1), {[Mn(6)O(2)(O(2)CCHMe(2))(10)(pyz)(3)] x H(2)O}(n) (2), and {[Mn(6)O(2)(O(2)CCHMe(2))(10)(Me(2)CHCO(2)H)(EtOH)(bpe)] x Me(2)CHCO(2)H}(n) (3) illustrates a surprising preference of the interlinked {Mn(6)} units toward 1D coordination chains. In the solid-state, the observed chain propagation axes are either colinear (1 and 3) or perpendicular (2), whereby crystal packing is further influenced by solvent molecules.