Syntheses and structural characterizations of the first coordination polymers assembled from the Ni(cyclam) 2+ cation and the benzene-1,3,5-tri-carboxyl-ate linker.

The asymmetric unit of catena -poly[[[(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ 4 N 1 , N 4 , N 8 , N 11 )nickel(II)]-μ 2 -5-carb-oxy-benzene-1,3-di-carboxyl-ato-κ 2 O 1 : O 3 ] octa-hydrate], {[Ni(C 9 H 4 O 6 )(C 10 H 24 N 4 )]·8H 2 O} n ( I ), consists of a macrocyclic Ni 2+ cation, a carboxyl-ate dianion and eight highly disordered water mol-ecules of crystallization. The components of the compound catena -poly[[[(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ 4 N 1 , N 4 , N 8 , N 11 )nickel(II)]-μ 2 -5-carb-oxy-benzene-1,3-di-carboxyl-ato-κ 2 O 1 : O 3 ] monohydrate], {[Ni(C 9 H 4 O 6 )(C 10 H 24 N 4 )]·H 2 O} n ( II ), are two crystallographically unique centrosymmetric macrocyclic dications, a carboxyl-ate dianion and one water mol-ecule of crystallization. In each compound, the metal ion is coordinated in the equatorial plane by the four secondary N atoms of the macrocyclic ligand, which adopts the most energetically stable trans -III conformation, and two mutually trans O atoms of the carboxyl-ate anions in a slightly tetra-gonally distorted trans -NiN 4 O 2 octa-hedral geometry. The crystals of both compounds are composed of parallel coordination polymeric chains running along the [010] direction in I and the [110] and [10] directions in II . The bridging carboxyl-ate anions display different modes of coordination connected with the relative orientation of coordinated O atoms, i.e. , remote in I and inter-mediate in II , thus resulting in essentially different distances between the Ni atoms in the chains [11.0657 (4) and 8.9089 (2) Å in I and II , respectively]. As a result of hydrogen-bonding inter-actions, the chains are joined together in sheets oriented parallel to the (10) and (001) planes in I and II , respectively.