title: An unusual coordination polymer containing Cu(+) ions and featuring possible Cu...Cu `cuprophilic' interactions: poly[di-μ-chlorido-(μ4-3,5-diaminobenzoato-κ(4)O:O':N:N')tricopper(I)(3 Cu-Cu)].
abstract: Compounds containing copper(I) are of interest for their role in biological processes. The nature of short (< ∼ 3.2 Å) Cu...Cu contacts within these compounds has been debated, being either described as weakly attractive (bonding) `cuprophilic' interactions, or simply as short metal-metal distances constrained by ligand geometry or largely ionic in nature. The title three-dimensional Cu(+)-containing coordination polymer, [Cu3(C7H7N2O2)Cl2]n, was formed from the in situ reduction of CuCl2 in the presence of 3,5-diaminobenzoic acid and KOH under hydrothermal conditions. Its complex crystal structure contains ten distinct Cu(I) atoms, two of which lie on crystallographic inversion centres. The copper coordination geometries include near-linear CuOCl and CuN2, T-shaped CuOCl2 and distorted tetrahedral CuOCl3 groups. Each Cu(I) atom is also associated with two adjacent metal atoms, with Cu...Cu distances varying from 2.7350 (14) to 3.2142 (13) Å; if all these are regarded as `cuprophilic' interactions, then infinite [-101] zigzag chains of Cu(I) atoms occur in the crystal. The structure is consolidated by N-H...Cl hydrogen bonds.
authors.affiliation: Department of Chemistry, Government College University, Faisalabad 38000, Pakistan.
authors.forename: Muhammad Kaleem
authors.initials: MK
authors.lastname: Khosa
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, England.
authors.forename: Paul T
authors.initials: PT
authors.lastname: Wood
authors.affiliation: Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station, Austin, Texas 78712, USA.
authors.forename: Simon M
authors.initials: SM
authors.lastname: Humphrey
authors.affiliation: Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, Scotland.
authors.forename: William T A
authors.initials: WT
authors.lastname: Harrison
mesh_terms: D062365:Aminobenzoates / Q000737:chemistry*; D056831:Coordination Complexes / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D007477:Ions / Q000737:chemistry; D008024:Ligands; D015394:Molecular Structure; D011108:Polymers / Q000737:chemistry*
chemical_list: D062365:Aminobenzoates; D056831:Coordination Complexes; D007477:Ions; D008024:Ligands; D011108:Polymers; C017856:3,5-diaminobenzoic acid; D003300:Copper; C029892:cupric chloride
keywords: 3,5-diaminobenzoate; copper(I); crystal structure; cuprophilic interaction; in situ reduction; three-dimensional coordination polymer