Bis(trimethyl­ammonium) tetra­chlorido­diphenyl­stannate(IV)

The title compound, [(CH3)3NH]2[Sn(C6H5)2Cl4], consists of [(CH3)3NH]+ cations and [SnPh2Cl4]2− anions in which the Sn atom, located on a centre of inversion, is bonded to four Cl atoms and two phenyl rings, giving an octa­hedral geometry with the phenyl rings in trans positions. In the crystal, the cations and the anions are connected by N—H⋯Cl hydrogen bonds and C—H⋯Cl inter­actions

Dibenzyl­aza­nium (oxalato-κ2 O,O′)triphenyl­stannate(IV)

The title compound, (C14H16N)[Sn(C6H5)3(C2O2)], was synthesised by allowing C2O4(Bz2NH2)2 (Bz = benzyl) to react with SnPh3Cl. The asymmetric unit is built up by four SnPh3C2O4 anions and four Bz2NH2 cations which are related by a pseudo-inversion centre. Each SnIV cation is five-coordinated by the three phenyl groups and two O atoms belonging to the chelating oxalate ligand; the coordination geometry is that of a distorted trigonal bipyramid. Anions and cations are linked through N—H⋯O hydrogen bonds into a layer structure parallel to (001). Moreover, the anion–cation pairs are associated by two bifurcated N—H⋯O hydrogen bonds, generating pseudo-dimers. One of the phenyl groups of one anion is disordered over two sets of sites in a 0.69:0.31 ratio. The Flack parameter value of 0.44 (1) indicates racemic twinning

Novel catalyst systems for deNOx

Belgium Herbarium image of Meise Botanic Garden

Tin(II) Ureide Complexes:Synthesis, Structural Chemistry and Evaluation as SnO precursors

In an attempt to tailor precursors for application in the deposition of phase pure SnO, we have evaluated a series of tin (1-6) ureide complexes. The complexes were successfully synthesized by employing N,N′-Trialkyl-functionalized ureide ligands, in which features such as stability, volatility, and decomposition could be modified with variation of the substituents on the ureide ligand in an attempt to find the complex with the ideal electronic, steric, or coordinative properties, which determine the fate of the final products. The tin(II) ureide complexes 1-6 were synthesized by direct reaction [Sn{NMe2}2] with aryl and alkyl isocyanates in a 1:2 molar ratio. All the complexes were characterized by NMR spectroscopy as well as elemental analysis and, where applicable, thermogravimetric (TG) analysis. The single-crystal X-ray diffraction studies of 2, 3, 4, and 6 revealed that the complexes crystallize in the monoclinic space group P2(1)/n (2 and 4) or in the triclinic space group P-1 (3 and 6) as monomers. Reaction with phenyl isocyanate results in the formation of the bimetallic species 5, which crystallizes in the triclinic space group P-1, a consequence of incomplete insertion into the Sn-NMe2 bonds, versus mesityl isocyanate, which produces a monomeric double insertion product, 6, under the same conditions, indicating a difference in reactivity between phenyl isocyanate and mesityl isocyanate with respect to insertion into Sn-NMe2 bonds. The metal centers in these complexes are all four-coordinate, displaying either distorted trigonal bipyramidal or trigonal bipyramidal geometries. The steric influence of the imido-ligand substituent has a clear effect on the coordination mode of the ureide ligands, with complexes 2 and 6, which contain the cyclohexyl and mesityl ligands, displaying κ2-O,N coordination modes, whereas κ2-N,N′ coordination modes are observed for the sterically bulkier tert-butyl and adamantyl derivatives, 3 and 4. The thermogravimetric analysis of the complexes 3 and 4 exhibited excellent physicochemical properties with clean single-step curves and low residual masses in their TG analyses suggesting their potential utility of these systems as MOCVD and ALD precursors.</p

Supramolecular organotin tris-carboxylates: Crystal and molecular structure of [Cy 2NH 2] 2[1-Me 3(H 2O)SnOCO-3,5-(OOC) 2C 6H 3]·EtOH

The crystal and molecular structure of [Cy2NH2]2[C6H3(CO2)3SnMe3·H2O]·CH3CH2OH (1) has been determined by single crystal X-ray diffraction analysis. In this compound, the tin atom is pentacoordinated by three methyl groups, one oxygen atom of a water molecule and one oxygen atom deriving from the tris-carboxylato ligand, in a trans-coordinated O2SnC3 environment. The dicyclohexylammonium cations are involved in intermolecular hydrogen bonds with the non-coordinated oxygen atoms of the carboxylate, while, along with hydrogen bonds involving water and ethanol, gives rise to a complex 3D lattice structure