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1.
Summary Reduction of anhydrous FeCl3 in THF with sodium naphthalenide under a CO atmosphere at room temperature leads directly to Na2Fe(CO)4, which on reaction with alkyl bromides gives the corresponding aldehydes, ketones and carboxylic acids under appropriate conditions. 相似文献
2.
A simple method for the synthesis of amines by the reduction of imines, anils and enamines, including some chiral substrates, with the MCl2/NaBH4/CH3OH reagent (M = Co, Ni) in 64–82% yields is described. 相似文献
3.
4.
A simple and convenient one-pot method for the reductive N-alkylation of (R,R)-trans-1,2-diaminocyclohexane by prochiral ketones using a Ti(OiPr)4/NaBH4 system to obtain the corresponding alkyl amine derivatives in 76–95% yields with good diastereoselectivity (dr = up to 23:1:1) is reported. 相似文献
5.
Background
Organic light emitting devices (OLED) are becoming important and characterisation of them, in terms of structure, charge distribution, and intermolecular interactions, is important. Tris(8-hydroxyquinolinato)-aluminium(III), known as Alq3, an organomettalic complex has become a reference material of great importance in OLED. It is important to elucidate the structural details of Alq3 in its various isomeric and solvated forms. Solid-state nuclear magnetic resonance (NMR) is a useful tool for this which can also complement the information obtained with X-ray diffraction studies. 相似文献6.
Nickel-silicon carbide composites were produced using 1 μm and 50 nm size powders from a conventional Watt's bath using tetra methyl ammonium hydroxide as the surfactant. Sediment codeposition technique with horizontal electrodes was used. The effect of silicon carbide concentration and bath operating parameters on the volume percents and deposition rates of coatings obtained with the two different particles was studied. Substantial improvements in mechanical properties such as hardness, wear resistance, scratch resistance and roughness were obtained with the nanocomposite material, as compared with composites containing microsized particles. 相似文献
7.
The aim of the present work was to study the corrosion inhibition of carbon steel using a ternary formulation. This new ternary inhibitor formulation, viz., 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC), with zinc ions and silicate ions was used to protect carbon steel from corrosion in a low-chloride environment. The gravimetric studies showed that 96 % inhibition efficiency was achieved with the ternary system consisting of 50 ppm PBTC, 50 ppm Zn2+ ions, and 10 ppm silicate ions. Out of 0.310 mmol of Zn2+ ions, 0.218 mmol was diffused from the bulk of the solution to the metal surface, as revealed from the studies of the solutions by atomic absorption spectroscopy (AAS). Electrochemical methods (potentiostatic polarization and electrochemical impedance spectroscopy) and surface characterization techniques [Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), and atomic force microscopy (AFM)] were used to ascertain the nature of the protective film and for explaining the mechanistic aspects of corrosion inhibition. 相似文献
8.
Mariappan Periasamy Subramaniapillai Selva Ganesan Surisetti Suresh 《Tetrahedron: Asymmetry》2010,21(4):385-392
β-Amino esters were obtained in up to 78% yield with 72:28–96:4 diastereomeric ratios by the reaction of the chiral titanium enolate of menthyl esters, prepared using the TiCl4/Et3N reagent system with prochiral imines. A representative syn-β-amino ester derivative has been used for the resolution of racemic mandelic acid to obtain a sample with >99% ee in a single step. A representative syn-β-amino ester was converted to the corresponding N-deprotected amino ester using the Pd–C/HCOOH reagent system, and then to the corresponding β-amino acid using the glacial CH3COOH/HCl reagent system, and to the corresponding β-lactam derivative with partial epimerization by the reaction using C2H5MgBr. 相似文献
9.
Hematoporphyrin IX dimethyl ester (HPDME), tetraphenylporphyrin (TPP), tetra(4-methoxyphenyl)porphyrin (TMPP), tetra(3,4-dimethoxyphenyl)porphyrin
(TDMPP), tetra(3,4,5-trimethoxyphenyl)porphyrin (TTMPP), tetraanthrylporphyrin (TAP) and tetraacridylporphyrin (TACP), and
their Zn2+, SnX
2
2+
, Pd2+ and Pt2+ complexes have been prepared and characterized. The singlet molecular oxygen quantum yield (ϕΔ) values of the above porphyrins and their metal derivatives in N,N-dimethyl formamide (DMF) have been measured in the presence
of 1,3-diphenylisobenzofuran (DPBF) as1O2 acceptor using steady state technique after correcting for the intensity of light absorbed by the photosensitizers. The ϕΔ values for the free base porphyrins are usually around 0.60. Hematoporphyrin IX dimethyl ester and its metal derivatives
follow the order: HPDME (ϕΔ = 0.60) > Zn HPDME (0.40) > PdHPDME (0.34) > Sn(OH)2 HPDME (0.28) > PtHPDME (0.24). Zinc(II) complexes of tetraarylporphyrins show about 65% efficiency in ϕΔ values are compared to the ϕΔ values of their corresponding free base porphyrins. These results can be explained on the basis of catalyzed intersystem
crossing to the ground state. The ϕλ values of the above free base porphyrins and their metal complexes in DMF in presence of DPBF using single-pulsed laser excitation
technique follow similar trends. 相似文献
10.
N. Periasamy 《Chemical physics letters》1983,99(4):322-325
The 00 band maximum of the transition T3(π, π*) ← T1 (π, π*) of acridine occurs at ≈ 10200 ± 20 cm?1 in inert (n-hexane, benzene, CCl4), at 10220 ± 20 cm?1 in polar (acetonitrile) and at 10170 ± 50 cm?1 in hydrogen-bonding (methanol, 2-propanol and alkaline water) solvents. Based on the solvent-independent energy of T1 (π, π*), the T3(π, π*) state of acridine is estimated at 26050 ± 50 cm?1 in all the solvents. 相似文献