title: Facile synthesis of novel two- and three-dimensional coordination polymers containing dialkyltin phosphonate-based tri/tetra-nuclear clusters with appended sulfonate groups.
abstract: The coordination-driven self-assemblies of mixed-ligand dialkyltin derivatives, [(Et(2)Sn)(4) (O(2)P(OH)Me)(2)(O(3)PMe)(2)(OSO(2)Et)(2) x 2 H(2)O](n) 1, [(Et(2)Sn)(3)(O(3)PMe)(2)(OSO(2)Me)(2) x CHCl(3)](n) 2, and [(Me(2)Sn)(3)(O(3)PBu(t))(2)(OSO(2)Me)(2) x 2 CHCl(3)](n) 3 have been achieved by reacting the tin precursors, [R(2)Sn(OR(1))(OSO(2)R(1))](n) (R = Et, R(1) = Et (1a), Me (2a); R = Me, R(1) = Me (3a)) with an equimolar amount of methylphosphonic/t-butylphosphonic acid under mild conditions (rt, 8 h, CH(2)Cl(2)). These have been characterized by IR and multinuclear ((1)H, (13)C, (31)P, and (119)Sn) NMR spectroscopy as well as single crystal X-ray diffraction. The asymmetric unit of 1 is composed of a tetranuclear, Sn(4)(mu(2)-PO(2))(2)(mu(3)-PO(3))(2) core bearing an appended ethanesulfonate group on each terminal tin (Sn2) atom and two P(OH)...O hydrogen bonded water molecules. The ladder-like structural motif thus formed is extended into one-dimensional polymeric chains by virtue of bridging bidentate mode of the sulfonate groups. These chains are linked by O-H...O(S) hydrogen bonds involving H(2)O molecules and oxygen atoms of the sulfonate groups. The asymmetric units of 2 and 3 are composed of trinuclear tin clusters with a Sn(3)(mu(3)-PO(3))(2) core and two dangling methanesulfonate groups which are covalently bonded to the tin centers. The construction of three-dimensional self-assemblies is effected by variable bonding modes (mu(2), mu(3) in 2; mu(2) in 3) of the methanesulfonate groups. Both the structural motifs possess five- and six-coordinated tin atoms and form rectangular channels which are occupied by CHCl(3) molecules.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Hauz Khas, New Delhi 110016, India. shankar@chemistry.iitd.ac.in
authors.forename: Ravi
authors.initials: R
authors.lastname: Shankar
authors.forename: Archana
authors.initials: A
authors.lastname: Jain
authors.forename: Atul Pratap
authors.initials: AP
authors.lastname: Singh
authors.forename: Gabriele
authors.initials: G
authors.lastname: Kociok-Köhn
authors.forename: Kieran C
authors.initials: KC
authors.lastname: Molloy
mesh_terms: D018360:Crystallography, X-Ray; D008024:Ligands; D008958:Models, Molecular; D063065:Organophosphonates / Q000737:chemistry*; D009947:Organotin Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013451:Sulfonic Acids / Q000737:chemistry*
chemical_list: D008024:Ligands; D063065:Organophosphonates; D009947:Organotin Compounds; D011108:Polymers; D013451:Sulfonic Acids