Volume 34, Issue 3-4

No abstract available

When H 2 SeO 3 is allowed to react with SnMe 2 Cl 2 in EtOH at a 1:2 ratio colorless crystals of HSeO 3 SnMe 2 Cl are obtained which have been characterized by X-ray crystallography. The compound crystallizes in triclinic space group P1 with cell parameters a=6.9693(5) Å, b=7.5096(4) Å, c=7.5222(5) Å, α=71.503(4)°, β=75.826(3)°, γ=87.114(4)°, Z=2, V=361.82(4) Å 3 . The structure consists of [Me 3 SnO 3 SeH] n chains in which Me 3 Sn units are bridged by the selenite ligand; chains are further linked into sheets by O—H----Cl bonds. The key role of hydrogen bonds is worth emphasizing.

The crystal structure of the title compound shows the [K(18-crown-6)] + cation and [{2,6-(Me 2 NCH 2 ) 2 C 6 H 3 }SnF 4 ] – anion, which are held together through two potassium–fluorine and one potassium–tin electrostatic interaction. The tin atom is hexacoordinated by one carbon and four fluorine atoms, and an intramolecular N→Sn interaction. It has a distorted octahedral configuration. Electrostatic interactions between two fluorine atoms and hydrogen atoms from two different cation–anion pairs generate a double-chain polymeric supramolecular structure, containing both isomers.

Some new 1,3-dihydro-1,3-dioxo-α-substituted-2H-isoindo­le-2-acetic acid derivatives of phenylboronic acid of compo­sitions PhBOH[O 2 CCH(R)C(O)] and PhB[O 2 CCH (R)(O)] 2 [where -CH(R)=-CH 2 CH 2 -, R=-CH 2 ­­C 6 H 5 , -CH(CH 3 ) 2 , and -CH(CH 3 )C 2 H 5 ] have been prepared by the reaction of phenylboronic acid with N-protected amino acids in 1:1 and 1:2 molar ratios in dry refluxing benzene. Plausible structures of these newly synthesized N-protected amino acid derivatives of phenylboronic acid have been proposed on the basis of physicochemical and spectroscopic studies. 11 B NMR data reveal the presence of tetracoordinated boron centers in these N-protected amino acid derivatives of phenylboronic acid.

Reactions of 2-hydroxy- N -phenylbenzamide with semicarbazide hydrochloride and thiosemicarbazide resulted in the formation of new ketimines, semicarbazone and thiosemicarbazone of 2-hydroxy- N -phenylbenzamide, respectively. The organogermanium(IV) complexes have been synthesized by reacting trimethylgermanium chloride and triphenylgermanium chloride in a 1:1 molar ratio with these ketimines using microwave as well as conventional heating method for comparison purposes. The authenticity of these ligands and their complexes has been established on the basis of elemental analysis, melting point determinations, molecular weight determinations, infrared, 1 H and 13 C nuclear magnetic resonance, ultraviolet, and mass spectral studies. These studies showed that the ketimines coordinated with the germanium atom and, accordingly, the trigonal bipyramidal environment around the metal atom has been established for the complexes. Both the ketimines and their complexes have been screened for their antimicrobial activities against a variety of fungal and bacterial strains and were found positive in this respect. The pesticidal activity of both the ligands and their metal complexes against the Corcyra cephalonica has also been tested.

A freshly distilled tin(IV) tetrachloride interacted with sodium salts of Schiff bases in 1:2 molar ratios in a mixture of tetrahydrofuron (THF)-C 6 H 6 produced complexes of the type [SnCl 2 (sb) 2 ], [where sb=Schiff bases; salicylidene-2-amino­pyridine (sap H ) (1) , salicylidene-2-amino-4-picoline (sapic H ) (2) , salicylidene-2-methyl-1-aminobenzene ( o -smab H ) (3) , salicylidene-4-methyl-1-aminobenzene ( p -smab H ) (4) , sali­cylidene-1-aminobenzene (sab H ) (5) , salicylidene-3-nitro-1-aminobenzene (snab H ) (6) ]. These complexes are soluble in polar solvents, monomeric, colored solids and characterized by elemental analysis (Sn, Cl, C, H, and N), spectral analysis [infrared and nuclear magnetic resonance ( 1 H, 13 C, and 119 Sn)], and time-of-flight mass spectrometry studies.

Reactions of methylbismuth(III) dichloride with thiosemicarbazones (TSC) in 1:1 and 1:2 molar ratios in anhydrous methanol yield [MeBiCl 2 .n{RR’CNNHCSNH 2 }] [where, R=R’=CH 3 and n=1 (1) or n=2 (2) ; R=C 6 H 4 OH, R’=H and n=1 (3) or n=2 (4) ; R=C 5 H 4 N, R’=CH 3 and n=1 (5) or n=2 (6) ]. These monomeric adducts have been characterized by elemental analyses, Fourier transform infrared, nuclear magnetic resonance [ 1 H, 13 C{ 1 H}] and fast atom bombardment mass spectrometry. The ligand appears to bind bismuth through sulfur and azomethine nitrogen atoms rendering penta- and hepta- coordination geometries, in (1, 3 and 5) and (2, 4 and 6 ) , respectively, in the solution state. Low temperature (143–145°C) solvothermal transformation of (3) or (4) in refluxing xylene yields nano-structured flowers of amorphous bismuthinite (Bi 2 S 3 ). Prolonged (~10 h) sintering at 150°C of the powder obtained from (4) yielded one-dimensional micro/nanorods of orthorhombic Bi 2 S 3 . All the materials were characterized by X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray analyses.