catena-Poly[[di-tert-butyl-tin(IV)]-μ-oxalato]

Synthesis, structure determination and characterization by UV-Vis and IR spectroscopy of bis-(diiso-propyl-ammonium) cis-di-chlorido-bis(oxalato-κ2 O 1,O 2)stannate(IV)

The organic-inorganic title salt, (C6H16N)2[Sn(C2O4)2Cl2] or ( i Pr2NH2)2[Sn(C2O4)2Cl2], was obtained by reacting bis-(diiso-propyl-ammonium) oxalate with tin(IV) chloride dihydrate in methanol. The SnIV atom is coordinated by two chelating oxalate ligands and two chloride ions in cis positions, giving rise to an [Sn(C2O4)2Cl2]2- anion (point group symmetry 2), with the SnIV atom in a slightly distorted octa-hedral coordination. The cohesion of the crystal structure is ensured by the formation of N-H⋯O hydrogen bonding between (iPr2NH2)+ cations and [SnCl2(C2O4)2]2- anions. This gives rise to an infinite chain structure extending parallel to [101]. The main inter-chain inter-actions are van der Waals forces. The electronic spectrum of the title compound displays only one high intensity band in the UV region assignable to ligand-metal ion charge-transfer (LMCT) transitions. An IR spectrum was also recorded and is discussed.

Crystal structure of (μ-trans-1,2-bis-{2-[(2-oxido-phen-yl)methyl-idene]hydrazin-1-yl-idene}ethane-1,2-diolato-κ3O,O',N)bis-[di-tert-butyl-tin(IV)]

The binuclear complex, [Sn2(C4H9)4(C16H10N4O4)], contains two Sn4+ ions, connected by doubly N-deprotonated oxalylbis[(2-oxido-benzyl-idene)hydrazide] ligands, and each Sn4+ ion is linked to two tert-butyl groups. The coordination sphere of each Sn atom is best described as a distorted trigonal bipyramid. Each stannic ion in the complex is in a C2O2N environment. The two homologous parts of the doubly deprotonated ligand are located in trans positions with respect to the C-C bond of the oxalamide group. The oxalamide group exhibits an asymmetric coordination geometry, as seen by the slight difference between the C-O and C-N bond lengths. The three-dimensional network is a multilayer of complex mol-ecules with no strong supramolecular inter-actions.

Crystal structure of bis-(diiso-propyl-ammonium) cis-di-iodido-bis-(oxolato-κ2O1,O2)stannate(IV)

In the title compound, (iPr2NH2)2[SnI2(C2O4)2], which was prepared by reacting ( i Pr2NH2+)2·C2O42- with SnI4 in a 2:1 molar ratio in a mixed ethanol-aceto-nitrile solvent, the Sn atom is coordinated by two chelating oxalate ions and two iodide ions, with the latter in a cis configuration. In the crystal, the cations are linked to the anions by N-H⋯O and bifurcated N-H⋯(O,O) hydrogen bonds, generating [10-1] chains.

Crystal structure of bis(cyclohexylammonium) diphenyldioxalatostannate(IV)

In the title salt, (CyNH₃)₂[Sn(Ph₂)(C₂O₄)₂] (Cy is cyclo­hexyl and Ph is phen­yl), the SnPh₂ moiety is chelated by two oxalate anions, leading to a cis arrangement within the distorted octa­hedral coordination sphere of the Sn^IV atom.

Reaction of oxalic acid and di­phenyl­tin dichloride in the presence of cyclo­hexyl­amine led to the formation of the title salt, (C₆H₁₄N)₂[Sn(C₆H₅)₂(C₂O₄)₂]. The dianion is made up from an Sn(C₆H₅)₂ moiety cis-coordinated by two chelating oxalate anions, leading to an overall distorted octa­hedral coordination geometry of the Sn^IV atom. The negative charges are compensated by two surrounding cyclo­hexyl­ammonium cations adopting chair conformations each. In the crystal, anions and cations are linked via a network of N—H⋯O hydrogen bonds into a layered arrangement parallel to (101).

Crystal structure of catena-poly[[aquadi-n-propyl-tin(IV)]-μ-oxalato]

The title compound, [Sn(C3H7)2(H2O)(C2O4)] n , represents the first diorganotin(IV) oxalate hydrate to be structurally characterized. The tin(IV) atom of the one-dimensional coordination polymer is located on a twofold rotation axis and is coordinated by two chelating oxalate ligands with two slightly different Sn-O bond lengths of 2.290 (2) and 2.365 (2) Å, two symmetry-related n-propyl groups with a Sn-C bond lengths of 2.127 (3) Å, and a water mol-ecule with a Sn-O bond length of 2.262 (2) Å. The coordination polyhedron around the Sn(IV) atom is a slightly distorted penta-gonal bipyramid with a nearly linear axis between the trans-oriented n-propyl groups [C-Sn-C = 176.8 (1)°]. The bond angles between the oxygen atoms of the equatorial plane range from 70.48 (6)° to 76.12 (8)°. A one-dimensional coordination polymer results from the less asymmetric bilateral coordination of the centrosymmetric oxalate anion, inter-nally reflected by two slightly different C-O bond lengths of 1.248 (3) and 1.254 (3) Å. The chains of the polymer propagate parallel to [001] and are held together by hydrogen bonds between water mol-ecules and oxalate anions of neighboring chains, leading to a two-dimensional network parallel to (100).

Reaction products of diorganotin(IV) oxides, R2SnO, with nitric acid. Part 2 – R = n-butyl and t-butyl

The reaction of diorganotin(IV) oxides, R2SnO with R = n-butyl and t-butyl, with nitric acid in different stoichiometric ratios resulted in the formation of different products depending on the organic groups attached to the tin atom: the diorganotin(IV) dinitrate dihydrates, n-Bu2Sn(NO3)2·2H2O (2d) and t-Bu2Sn(NO3)2·2H2O (2e), the mixed diorganotin(IV) nitrate methoxide oxide n-Bu2Sn(NO3)(n-Bu2SnOMe)O (6), and the diorganotin(IV) nitrate hydroxide hydrate t-Bu2Sn(NO3)(OH)·H2O = [t-Bu2Sn(OH)(H2O)][NO3] (7). On examination of the solubility of the primary reaction products in different solvents, the three additional compounds t-Bu2Sn(NO3)(OH)·DMSO (8), t-Bu2Sn(NO3)(OH)·THF, and 2-t-Bu2Sn(NO3)(OH)·DMF = [t-Bu2Sn(OH)dmf]2[NO3]2·[t-Bu2Sn(NO3)OH]2 (9) could be isolated. All compounds have been structurally characterized by single crystal X-ray diffraction (primary results for 7) with special attention paid to dimensionality (2d and 2c = monomeric, hydrogen bonded molecules; 6 = dimeric molecules of ladder-type structure; 7 = dimeric cation; 8 = dimeric molecule with hydrogen bonded solvent molecules; 9 = both components dimeric), tin coordination (6, 7, 8, and 9 = trigonal bipyramidal; 2d and 2e = eightfold), and nitrate bonding modes (7 and 9 = isolated, hydrogen bonded; 6, 8, and 9 (component 2) = monodentate; 2d and 2e = symmetrical bidentate), the latter one being analyzed using both Sn–O and N–O distances.