Dipotassium biphenyl-4,4′-disulfonate dihydrate: a coordination polymer

Abstract

The polymeric structure of the title compound, poly[[diaquabis(μ‐biphenyl‐4,4′‐disulfonato)tetrapotassium(I)] dihydrate], {[K2(C12H8O6S2)(H2O)]·H2O}n, is based on an asymmetric unit comprising three independent and different potassium centres, one six‐coordinate [K—O = 2.657 (3)–2.866 (5) Å], one seven‐coordinate [K—O = 2.703 (3)–3.040 (4) Å], and the third ten‐coordinate [K—O = 2.751 (3)–3.079 (4) Å], with two of these lying on crystallographic mirror planes. The four half‐occupancy water molecules also lie on the mirror planes with two coordinated (one monodentate, the other bidentate bridging) and two as molecules of solvation. The interlinked coordination polyhedra form chains which are joined laterally through the biphenyl residues as well as through head‐to‐tail water hydrogen‐bonding interactions, giving a two‐dimensional structure.

Crystal structure of dilithium biphenyl-4,4′-disulfonate dihydrate

“…Thus, each sulfonate group coordinates to three Li cations to obtain a di-periodic layer. The bond distances between the Li cation and the oxygen atoms lie in the range 1.901 (5)-1.944 (5) A ˚at angles of 103.7 (2)-114.8 (2) � , which are shorter than those of reported Na 2 -disulfonate [2.313 (3)-2.560 (3) A ˚] and K 2 -disulfonate [2.657 (3)-3.079 (4) A ˚] complexes (Albat & Stock 2016;Smith et al, 2007). Similar trends of bond distances are observed in alkali metal-carboxylate network materials (Banerjee & Parise, 2011).…”

“…A survey of the Cambridge Structural Database (CSD, v5.44, April 2023; Groom et al, 2016) for structures with biphenyl and sulfonate and alkali metals resulted in seven hits. Of these, the alkali metal-coordinated compounds are a potassium complex (HIQKEY; Smith et al, 2007), which is related to this work, and a sodium complex (SIWVUP; Anderson et al, 1998). No coordination bonds are found in other alkali-metal salts.…”