Synthesis and spectroscopic characterization of some lanthanide(III) nitrate complexes of ethyl 2-[2-(1-acetyl-2-oxopropyl)azo]-4,5-dimethyl-3-thiophenecarboxyate

Ethyl 2-[2-(1-acetyl-2-oxopropyl)azo]-4,5-dimethyl-3-thiophenecarboxyate was synthesized by coupling diazotized ethyl 2-amino-4,5-dimethylthiophene-3-carboxylate with acetylacetone. Based on various spectral studies and elemental analysis, an intramolecularly hydrogen-bonded azo-enol structural form was assigned for the ligand. This ligand is versatile in forming a series of lanthanide(III) complexes, viz., lanthanum(III), cerium(III), praseodymium(III), neodymium(III), samarium(III) and gadolinium(III), which were characterized through various spectral studies, elemental analysis, magnetic susceptibility measurements, molar conductance and thermal analysis. The spectral data revealed that the ligand acted as a neutral tridentate, coordinating to the metal ion through one of the azo nitrogen atoms, the ester carbonyl and the enolic oxygen of the acetylacetone moiety, without deprotonation. Molar conductance values adequately supported their non-electrolytic nature. The ligand and lanthanum(III) complex were subjected to X-ray diffraction studies. In addition, the lanthanum(III) complex underwent a facile transesterification reaction on refluxing with methanol for a long period. The thermal behaviour of the lanthanum(III) complex was also examine

Doping-less Tunnel Field Effect Transistor: Design and Investigation

Using calibrated simulations, we report a detailed study of the doping-less tunnel field effect transistor (TFET) on a thin intrinsic silicon film using charge plasma concept. Without the need for any doping, the source and drain regions are formed using the charge plasma concept by choosing appropriate work functions for the source and drain metal electrodes. Our results show that the performance of the doping-less TFET is similar to that of a corresponding doped TFET. The doping-less TFET is expected to be free from problems associated with random dopant fluctuations. Further, fabrication of doping-less TFET does not require high-temperature doping/annealing processes and therefore, cuts down the thermal budget opening up the possibilities for fabricating TFETs on single crystal silicon-on-glass substrates formed by wafer scale epitaxial transfer

Synthesis, spectroscopic characterisation, corrosion inhibition studies and dyeing properties of lanthanide(III) complexes of 1-[(3-carboxyethyl-4,5-dimethylthiophen-2-yl)azo]-2-naphthol

Ligational behaviour of the heterocyclic ligand obtained by coupling of diazotized 2-amino-3-carboxyethyl-4,5-dimethylthiophene with β-naphthol towards some selected lanthanide(III) ions has been studied. Various spectral and physico-chemical techniques have been used to confirm the coordination sites of the ligand (HTAN) and its lanthanide(III) complexes. It has been observed that these ligands coordinate to the metal ions in a neutral tridentate fashion. Thermal stability of metal chelates and structural stability of the chelating agent has been studied by thermal analysis. As lanthanides and azo dyes are reported as good corrosion inhibitors we have examined the corrosion inhibition activities of HTAN and its metal complexes. Also dyeing properties of the azo dye and some of its selected complexes towards cotton fabrics has been evaluated, as the traditional application field of the synthetic azo dyes still remains in the textile industry

Synthesis and spectroscopic characterization of some lanthanide(III) nitrate complexes of 3-[3-carboxyethyl-4,5- dimethylthiophene-2-yl)azo]pent-2,4-dione

3-[3-Carboxyethyl-4,5-dimethylthiophene-2-yl)azo]pent-2,4-dione was synthesized by coupling diazotized 2-amino-3-carboxyethyl- 4,5-dimethylthiophene with acetylacetone. Based on various spectral studies and elemental analysis, an intramolecularly hydrogen bonded azoenol structural form was assigned for the ligand. This ligand is versatile in forming a series of lanthanide(III) complexes viz, lanthanum(III), cerium(III), praseodymium(III), neodymium(III), samarium(III) and gadolinium(III), which were characterized through various spectral studies, elemental analysis, magnetic susceptibility measurements, molar conductance and thermal analysis. The spectral data revealed that the ligand acted as a neutral tridentate, coordinating to the metal ion through one of the azo nitrogen atoms, the ester carbonyl and the enolic oxygen of the acetylacetone moiety, without deprotonation. Molar conductance values adequately supported their non-electrolytic nature. The ligand and lanthanum(III) complexes were subjected to X-ray diffraction studies. In addition, the lanthanum(III) complex underwent a facile transesterification reaction on refluxing with methanol for a long period. The thermal behavior of the lanthanum(III) complex was also examined.</jats:p

A facile Michael addition reaction of β-diketones to nitrostyrenes: alkylamino substituted triazine as an efficient organocatalyst

Various aminoalkyl substituted triazines have been synthesised and their activity as organocatalyst has been studied in the Michael addition reactions of β-diketones to nitrostyrenes. All the catalysts were found to be effective towards the addition reaction, and highest performance was achieved with the catalyst having long chain alkyl group. The effect of base and solvent has also been investigated, and the condition has been optimized with triethylamine as the base and chlorobenzene as the solvent for excellent yields. The reaction is highly remarkable since the catalyst under study is readily available and inexpensive compared to other organocatalyst known for the reaction

A facile Michael addition reaction of β-diketones to nitrostyrenes: Alkylamino substituted triazine as an efficient organocatalyst

1316-1322Various aminoalkyl substituted triazines have been synthesised and their activity as organocatalyst has been studied in Michael addition reactions of β-diketones to nitrostyrenes. All the catalysts are found to be effective towards the addition reaction and highest performance is achieved with the catalyst having long chain alkyl group. The effect of base and solvent has also been investigated, and the condition has been optimized with triethylamine as the base and chlorobenzene as the solvent for excellent yields. The reaction is highly remarkable since the catalyst under study is readily available and inexpensive compared to other organocatalyst known for the reaction