Homo‐ and Heterometallic Coordination Oligomers and Polymers Derived from the Preformed Complexes [Cu(bdmpp)(MeCN) 2 ](ClO 4 ) 2 , [Cu(bdmpp)(N 3 ) 2 ], and [Cu(bdmpp)(N 3 )(μ‐N 3 )] 2 [bdmpp = 2,6‐bis(3,5‐dimethyl‐1 H ‐pyrazol‐1‐yl)pyridine]: Syntheses, Structures, and Redox Properties

Reactions of three Cu II complexes of 2,6‐bis(3,5‐dimethyl‐1 H ‐pyrazol‐1‐yl)pyridine (bdmpp), [Cu(bdmpp)(MeCN) 2 ](ClO 4 ) 2 ( 1 ), [Cu(bdmpp)(N 3 ) 2 ] · 1.5H 2 O ( 2· 1.5H 2 O), and [Cu(bdmpp)(N 3 )(μ‐N 3 )] 2 · 2MeOH ( 3· 2MeOH), with 4,4′‐bipy, dicyanamide (dca), azide, and MCl 2 (M = Cu, Co, Ni) yield a series of homo‐ and heterometallic coordination oligomers and polymers, [{Cu(bdmpp)(ClO 4 )} 2 (μ‐4,4′‐bipy)](ClO 4 ) 2 ( 4 ), {[Cu(bdmpp)(μ‐dca)](ClO 4 )} n ( 5 ), {[Cu(bdmpp)(μ‐N 3 )](ClO 4 ) · MeCN} n ( 6 ), [{Cu(N 3 )(bdmpp)} 2 (μ‐N 3 ) 2 Cu(N 3 ) 2 ] ( 7 ), and [{Cu(μ‐N 3 )(bdmpp)(μ‐N 3 )M(μ‐N 3 )(X)} 2 · e MeCN] n ( 8 : M = Co, X = N 3 , e = 0; 9 : M = Ni, X = Cl; e = 4). Compounds 1 – 9 have been characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray crystallography. Compound 4 has a centrosymmetric dimeric dication structure in which two [Cu(bdmpp)(ClO 4 )] + fragments are bridged by one 4,4′‐bipy. Compounds 5 and 6 have a 1D linear or spiral chain extending along the b axis in which each [Cu(bdmpp)] 2+ fragment is linked through bridging dca or azide anions, respectively. Compound 7 has a trinuclear sandwich structure in which two molecules of 2 link a Cu(N 3 ) 2 species through two end‐on bridging azide anions. Compounds 8 and 9 have a similar 1D chain structure extending along the c axis in which [Cu(μ‐N 3 )(bdmpp)(μ‐N 3 )M(μ‐N 3 )(X)] 2 (M = Co, Ni) molecules are linked by end‐to‐end azide anions ( 8 ) or end‐on azide anions ( 9 ). In addition, the electrochemical properties of 1 – 9 in DMF were investigated by cyclic voltammetry. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)