Crystal structure of the one-dimensional coordination polymer formed by the macrocyclic [Ni(cyclam)]²⁺cation and the dianion of diphenylsilanediylbis(4-benzoic acid)

Abstract

The asymmetric unit of the title compound, catena-poly[[[(1,4,8,11-tetraazacyclotetradecane-κ4 N 1,N 4,N 8,N 11)nickel(II)]-μ-4,4′-(diphenylsilanediyl)dibenzoato-κ2 O:O′] sesquihydrate], {[Ni(C26H18O4Si)(C10H24N4)]·1.5H2O} n , consists of the halves of the centrosymmetric macrocyclic cation and the C 2-symmetric dicarboxylate dianion and of the water molecule of crystallization. The Ni2+ ion is coordinated by the four secondary N atoms of the macrocyclic ligand characterized by the most energetically favourable trans-III conformation and two mutually trans O atoms of the carboxylate, forming a slightly tetragonally elongated trans-N4O2 octahedron. The crystals are composed of parallel polymeric chains of the macrocyclic cations linked by the anions of the acid running along the [101] direction. Each polymeric chain is bonded to four neighbouring ones via water molecules providing O—H...O hydrogen bonds to the non-coordinated carboxyl O atoms to form a three-dimensional supramolecular network.

From Amorphous Silicones to Si-Containing Highly Ordered Polymers: Some Romanian Contributions in the Field

“…However, highly ordered, crystalline polymeric covalent structures, where siloxane motifs alternate with coordinated metal blocks, were obtained with carboxylic ligands, 1,3-bis(carboxypropyl)tetramethyldisiloxane (H 2 CX) prepared for the first time in 1999 [ 15 ], bis(p-carboxyphenyl)diphenylsilane (H 2 L 1 ), and bis(3,4-dicarboxyphenyl)dimethylsilane (H 4 L 2 ) were prepared later [ 126 ] ( Figure 9 a). They were used alone to directly coordinate the metal ions [ 127 , 128 , 129 ] or complexes of the latter with vacancies [ 55 , 99 , 130 , 131 ] or in combination with ancillary organic ligands (imidazole [ 132 , 133 ], 4,4′-bipyridyl [ 134 ], 4,4′-azopyridine [ 56 , 132 , 135 ], 1,2-di(4-pyridyl)ethylene [ 134 ], 1,10-phenanthroline [ 126 ], etc.) ( Figure 9 b) and metal ions or clusters, which allow highly directional intermolecular interactions (metal-ligand, hydrogen bonds and π-π stacking interactions).…”

“…The flexibility of this segment allows the adoption of both cis - [ 133 , 135 ], and trans -oide [ 55 , 133 , 135 ] conformations, in dependence on the coordination geometry of the secondary building units (SBUs) and H-bonding configuration. It was observed that while the complexation of metals with silicone ligands almost always leads to 1D structures [ 55 , 99 , 128 , 131 , 132 , 134 ], in the presence of an organic co-ligand 2D structures are often formed [ 56 , 127 , 132 , 133 , 134 , 135 ]. The 2D structures built with the H 2 Cx ligand are of interest from the perspective of 2D materials, presenting as hydrophobic nano-sheets with very weak interactions between them [ 56 ].…”

“…Carboxylic ligands containing silicon in the substrate (a) and organic co-ligands (b) used; 1D coordination polymer based on: diphenylsilane-spaced dicarboxylate (H2L1 ligand) coordinated to the NiL [131] (c), tetramethyl-Figure 9. Carboxylic ligands containing silicon in the substrate (a) and organic co-ligands (b) used; 1D coordination polymer based on: diphenylsilane-spaced dicarboxylate (H 2 L 1 ligand) coordinated to the NiL[131] (c), tetramethyldisiloxane-spaced dicarboxylate (H 2 CX ligand) coordinated to the NiL preformed complex[130] (d) and to oxime-bridged Mn 6+ cluster[55] (e); Covalent 2D coordination polymers looking like nano-sheets consisting of: dimanganese coordinated by H 2 CX and 4,4'-azopyridine[56] (f); trinuclear (g) and pentanuclear (h) manganese coordinated with H 2 L 1[127].…”

A new 1D Mn(II) coordination polymer: Synthesis, crystal structure, hirshfeld surface analysis and molecular docking studies

“…Topological analogs exhibit similar connectivity patterns with variations in ligands or metal ions. Structural analogs display similar overall structures with differences in ligand or metal ion arrangements [ [26] , [27] , [28] ].…”