Syntheses, Crystal Structures and Magnetic Properties of Carboxylato‐Bridged Polymeric Networks of Mn II

Three new carboxylato‐bridged polymeric networks of Mn II having molecular formula [Mn(ox)(dpyo)] n ( 1 ), {[Mn 2 (mal) 2 (bpee)(H 2 O) 2 ] · 0.5(bpee) · 0.5(CH 3 OH)} n ( 2 ) and {[Mn 3 (btc) 2 (2,2′‐bipy) 2 (H 2 O) 6 ] · 4H 2 O} n ( 3 ) [dpyo, 4,4′‐bipyridine N , N ′‐dioxide; bpee, trans ‐1,2 bis(4‐pyridyl)ethylene; 2,2′‐bipy, 2,2′‐bipyridine; ox = oxalate dianion; mal = malonate dianion; btc = 1,3,5‐benzenetricarboxylate trianion] have been synthesized and characterized by single‐crystal X‐ray diffraction studies and low temperature magnetic measurements. Structure determination of complex 1 reveals a covalent bonded 2D network containing bischelating oxalate and bridging dpyo; complex 2 is a covalent bonded 3D polymeric architecture, formed by bridging malonate and bpee ligands, resulting in an open framework with channels filled by uncoordinated disordered bpee and methanol molecules. Whereas complex 3 , comprising btc anions bound to three metal centers, is a 1D chain which further extends its dimensionality to 3D via ‐ and H‐bonding interactions. Low temperature magnetic measurements reveal the existence of weak antiferromagnetic interaction in all these complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)