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Abstract: The surfactant sodium bis(2-ethylhexyl) sulfosuccinate based tin(IV) phosphate (AOT-SnP) fibrous ion exchanger has been synthesized and characterized by using different physico-chemical methods. The characterization of the exchanger was performed by using infrared (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and elemental analysis. The ion exchange property was studied by determining the ion exchange capacity, elution and concentration behavior of the cation exchanger. The thermal behavior of exchanger was studied by performing ion exchange capacity at different temperatures. Adsorption studies on the synthesized material showed that it is highly selective for Cd2+, Zn2+and Hg2+ ions. Therefore, the separation of Cd2+, Zn2+and Hg2+ ions from the synthetic waste water has been performed on its column and observed to be quite effective in presence of acid, alkali, alkaline earth and other transition metals. [Copyright &y& Elsevier]

Abstract: A racemic synthesis of the ABCD ring core of the ambiguines that preserves the tertiary alcohol has been accomplished in a convergent synthesis in 10 synthetic steps, in an overall yield of 46% from commercially available 4-bromoindole and m-methylanisole. [Copyright &y& Elsevier]

Abstract: The reaction of meso-tetraarylporphyrins (H2T(X)PP) with SnCl4 affords green intermediate sitting-atop (i-SAT) complexes, [(H2T(X)PP)SnCl4]. UV–Vis, 1H NMR and 13C NMR spectral data show that the porphyrin core of the complexes is distorted, thus two nitrogen atoms of the pyrrolenine groups on one side of the porphyrin plane act as electron donors to the tin center of SnCl4. The intermediate sitting-atop (i-SAT) complex is formed each time during the incorporation of the metal center, where in the intermediate state the pyrrolic protons still remain on the porphyrin. [Copyright &y& Elsevier]

Abstract: The two octahedral complexes SnCl4 ·2(O)P(NR2)2OCH2CF3 (R=Me (1) or Et (2)) have been prepared from SnCl4 and the ligands (R2N)2P(O)OCH2CF3 in chloroform solution. Both adducts have been characterised by (31P and 119Sn) NMR, IR spectroscopy and elemental analysis. The NMR data show that the complexes exist as mixtures of cis and trans isomers in solution with the latter isomer being the predominant species. The structure of 1 has been determined by X-ray crystallography. Accordingly, the structure is centrosymmetric and the two ligands are bound trans to each other in the octahedral tin complex. DFT/B3LYP calculations show that trans configuration does indeed lead to the lowest energy species. Comparison of the structural, NMR and theoretical data of both complexes with those related to SnCl4 ·2L (L=(Me2N)3P(O) and (Me2N)2P(O)F) further supports the important effects of the nature of the substituents in the ligand on the stereochemistry of the complex formed. [Copyright &y& Elsevier]

The compounds [SnCl4(L)n] (where L is pyridine (py), 4-methylpyridine (γ-pico), 3-methylpyridine (β-pico), piperidine (pipd), morpholine (morph), piperazine (pipz), 3-cyanopyridine (3-cyanopy), 4-cyanopyridine (4-cyanopy), quinoline (quin) or 2,2′-bipyridine (bipy) and n=2, 1 or 3/2) were synthesized and characterized by elemental analysis, melting points, thermal studies and IR spectroscopy. The enthalpies of dissolution of adducts, tin(IV) chloride and ligands in 1,2-dichloroethane or 25% (v/v) aqueous HCl 1.2 M in methanol were measured and, by using thermochemical cycles, the following thermochemical parameters for the adducts have been determined: the standard enthalpies for the Lewis acid/base reaction (ΔrH°), the standard enthalpies of formation (ΔfH°), the standard enthalpies of decomposition (ΔDH°), the lattice standard enthalpies (ΔMH°) and the standard enthalpies for the Lewis acid/base reaction in the gaseous phase (ΔrH°). The mean standard enthalpies of the tin–nitrogen bonds (D¯(Sn–N)) have been estimated. Based on these last values, the basicity orders: pipd>morph>γ-pico=β-pico>py>4-cyanopy>3-cyanopy and pipz>quin are obtained. [Copyright &y& Elsevier]

Tin(IV) chloride selectively promotes the nucleophilic attack of methyl acetoacetate to the cyano instead of the olefinic carbon atom of α,β-unsaturated nitriles to give enaminoketoesters. In the presence of an excess of ketoester a second C–C bond formation occurs followed by cyclisation affording substituted pyridines in a selective cascade sequence. [Copyright &y& Elsevier]

• Chiral acetamide oxazolidinones produced. • Reactions with indoles gave pyrroloindoline products. • This structure is found in many natural products. • Numerous indoles gave up to 91% yield with high selectivity. Chiral N- 2-acetamidoacrylyl oxazolidinones were produced and reacted with indoles under Lewis acid conditions to generate hexahydropyrrolo[2,3- b indole products in a formal [3 + 2] cycloaddition process. Optimal conditions included the use of tin(IV) chloride in methylene chloride at 0 °C. Pyrroloindoline products were obtained from various indoles with shorter reaction times (12 hr) up to 91% yield with high, >20:1 exo selectivity. A mechanism involving reversible conjugate addition followed by an enamine lone-pair-iminium capture, tautomerization, and tin-enolate protonation accounts for the selectivity. The method enables selective applications to pyrroloindoline targets and further refinement with chiral catalysts. [ABSTRACT FROM AUTHOR]

2-Propenyl tin species, prepared from 3-halopropenes or 2-propenyl mesylate with tin(IV) chloride and tetrabutylammonium iodide in dichloromethane, causes nucleophilic addition to aldehydes to produce the corresponding homoallylic alcohols. [Copyright &y& Elsevier]