Synthesis and crystal structure of poly[[di-μ₃-tetrathioantimonato-tris[(cyclam)cobalt(II)]] acetonitrile disolvate dihydrate] (cyclam = 1,4,8,11-tetraazacyclotetradecane)

Abstract

Reaction of Co(ClO4)2·6H2O with cyclam (cyclam = 1,4,8,11-tetraazacyclotetradecane) and Na3SbS4·9H2O (Schlippesches salt) in a mixture of acetonitrile and water leads to the formation of crystals of the title compound with the composition {[Co3(SbS4)2(C10H24N4)3]·2CH3CN·2H2O} n or {[(Co-cyclam)3(SbS4)2]·2(acetonitrile)·2H2O} n . The crystal structure of the title compound consists of three crystallographically independent [Co-cyclam]2+ cations, which are located on centers of inversion, one [SbS4]3− anion, one water and one acetonitrile molecule that occupy general positions. The acetonitrile molecule is disordered over two orientations and was refined using a split model. The CoII cations are coordinated by four N atoms of the cyclam ligand and two trans-S atoms of the tetrathioantimonate anion within slightly distorted octahedra. The unique [SbS4]3− anion is coordinated to all three crystallographically independent CoII cations and this unit, with its symmetry-related counterparts, forms rings composed of six Co-cyclam cations and six tetrathioantimonate anions that are further condensed into layers. These layers are perfectly stacked onto each other so that channels are formed in which acetontrile solvate molecules that are hydrogen bonded to the anions are embedded. The water solvate molecules are located between the layers and are connected to the cyclam ligands and the [SbS4]3− anions via intermolecular N—H...O and O—H...S hydrogen bonding.

Crystal structure of μ3-tetrathioantimonato-tris[(cyclam)zinc(II)] tetrathioantimonate acetonitrile disolvate dihydrate showing Zn disorder over the cyclam ring planes (cyclam = 1,4,8,11-tetraazacyclotetradecane)

“…1). In contrast to [(Cu-cyclam) 3 (SbS 4 ) 2 ]Á20H 2 O (Danker et al, 2021) and [(Cocyclam) 3 (SbS 4 ) 2 ](H 2 O) 2 (acetonitrile) 2 (Na ¨ther et al, 2022), in both of which the cations are located at the center of the cyclam ligand and have an octahedral coordination, in the title compound the Zn 2+ cations are shifted out of the N 4 plane of the ligand by 0.4318 (6) A ˚(Zn1), 0.3751 (6) A ˚(Zn2) and 0.4998 (7) A ˚(Zn3). This means that each Zn 2+ cation is in a…”

“…The formed complex cations are in a fourfold coordination environment and provide additional coordination sites for thioantimonate anions, which can lead to the formation of networks by (TMC)-S bonds to the anion. Following this synthetic approach, we reacted cyclam with Na 3 SbS 4 Á9H 2 O and different transition-metal salts, which led to the formation of compounds with compositions: (Danker et al, 2021) and [(Co-cyclam) (Na ¨ther et al, 2022). In the crystal structure of the cobalt and copper compounds, the metal cations are octahedrally coordinated by the four N atoms of the cyclam ligand and by two S atoms of the tetrathioantimonate(V) anions in trans-positions.…”