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161.
A variety of activated and non-activated secondary alcohols have been efficiently oxidized to their corresponding ketones in excellent yields with molecular oxygen using cobalt phthalocyanine as catalyst in the presence of powdered potassium hydroxide. 相似文献
162.
Sunil B. Zanje Vishal J. Suryavanshi Arjun N. Kokare Anita A. Ghare Ganesh S. Kamble Pravin N. Kamble Mansing A. Anuse 《Journal of Analytical Chemistry》2018,73(5):438-451
A simple, rapid, selective, sensitive and reliable extractive spectrophotometric method was developed for the determination of ruthenium(III) using 2-nitrobenzaldehyde thiocarbohydrazone (2-NBATCH) as a chromogenic chelating ligand. The ruthenium(III)?2-NBATCH complex is formed in aqueous acetic acid media (0.7 M) containing an organic solvent after 5 min heating on a water bath. The red colored complex is extracted into 1,2-dichloroethane and absorbance is measured at 445 nm against reagent blank. The Beer’s law is obeyed within 1?6 g/mL of ruthenium(III), the optimum concentration range was 2?5 g/mL of ruthenium(III) evaluated by Ringbom’s plot. Molar absorptivity and Sandell’s sensitivity of complex were 1.41 × 104 L/mol/cm and 0.0075 μg/cm2, respectively. The stoichiometry of complex was 1: 3 established from Job’s method of continuous variation, molar ratio method and logarithmic slope method. The proposed method was applied for determination of ruthenium(III) in binary and ternary, synthetic mixtures corresponding to fission product elements alloy and ruthenium(III) catalysts. 相似文献
163.
Rukhsana I. Kureshy Surendra Singh Noor-ul H. Khan Sayed H.R. Abdi Santosh Agrawal Vishal J. Mayani Raksh V. Jasra 《Tetrahedron letters》2006,47(30):5277-5279
Catalytic asymmetric ring opening of cyclohexene oxide and meso-stilbene oxide with anilines was catalyzed by a Ti-(S)-(−)-BINOL complex to afford β-amino alcohols in high yield (up to 95%) and good enantioselectivities (ee up to 55%) under microwave irradiation. The reaction using a microwave was found to be 10 times faster than traditional oil-bath heating with retention of enantioselectivity. 相似文献
164.
Vishal A. Mahajan 《Tetrahedron letters》2005,46(6):1009-1012
A synthesis of novel 4-(substituted)benzyl-5-methylene-2(5H)-furanones involving Stobbe condensation of substituted aldehydes with ethyl levulinate followed by treatment with acetic anhydride in the presence of sodium acetate, has been developed. 相似文献
165.
The folding space for all the protein sequences is limited. Therefore it was observed that many proteins, whose sequences are not related, have similar fold characteristics. The fold databases like SCOP and CATH have classified various protein folds. However, in-depth analysis of the functional features of these folds was not done. We analyzed about twenty unique SH3-like folded proteins in their structural environment and functional characteristics. From our analysis it is apparent that the SH3-like folds could carry out various functions by modulation of loops and the functional region is restricted to one side of a particular sheet helped by two or three loops. The functions vary from oligonucleotide-binding to peptide-binding and other ligand binding. Although certain degree of sequence similarity was observed among the SH3-fold proteins, the similarity was restricted to the beta-strand regions of the proteins. 相似文献
166.
A new ligand, 1-(2-furanthiocarbo)-3-thiosemicarbazide (H2ftsc), prepared from thiosemicarbazide and carboxymethyl-2-furandithioate, forms complexes [Mn(ftsc)(H2O)2], [Pd(ftsc)] · 2H2O, [M(Hftsc)(acac)2] (M=CoIII or CrIII), [M(Hftsc)2(acac)] (M=MnIII or FeIII) and [Zn(Hftsc)2] · 2H2O, which were characterized by elemental analyses, magnetic susceptibility, i.r., electronic and n.m.r. spectral data. The Mössbauer spectra of [Fe(Hftsc)2(acac)] at 298K and 80K suggest the presence of high-spin iron(III) with an S=5/2 state. In vivo and in vitro antitumour activity of the ligand and the complexes have been screened towards several tumour cell-lines. 相似文献
167.
In this paper we present a comparative study of inelastic interactions of C12-Em and p-Em at 4·5 GeV/c per nucleon. The multiplicity distributions and their correlations have been studied. The results show a strong correlation of n
s onn
h in the case of C12-Em but not in the case of p-Em. It is also shown that the n
s increases with the increase of the projectile mass. The angular distribution of the target fragments in C12-Em shows a massive forward collimation. Comparison is also made in the pseudorapidity distribution of both C12-Em and p-Em, the result shows many interesting features. 相似文献
168.
The debromination of α-bromoketones with an easily accessible ionic liquid, 1-methyl-3-pentylimidazolium tetrafluoroborate, [pmIm]BF4 under microwave irradiation has been investigated. By controlling the reaction time gem-α-dibromoketones are selectively debrominated to either monobromo or debromoketones. The α-monobromo- and α-monoiodoketones are dehalogenated while the corresponding chloroketones remain inert. The activated vic-bromoacetates are converted to the corresponding (E)-alkenes by the same procedure. These reactions do not require any organic solvent, any metal or any conventional reducing agent. The ionic liquid works here as catalyst as well as reaction medium and is recycled without any appreciable loss of its catalytic efficiency. 相似文献
169.
Experimental determination of density, ultrasonic velocity and viscosity of two pyrimidine bases thymine and cytosine along with their respective nucleosides, thymidine and cytidine has been carried out in aqueous urea solutions in the presence of different concentrations of three salts, viz. NaCl, KCl and CaCl2. The experimental data have been used for the
computation of various thermodynamic parameters, viz. apparent molar volume, apparent molar compressibility, coefficients A and B of the Jones-Dole equation, internal pressure, acoustic impedance, etc. Structural studies of solutions under investigation have also been carried out by ultraviolet spectroscopy, and an attempt has been made to collaborate the
findings of ultraviolet spectroscopy with results obtained thermodynamically. 相似文献
170.
Summary Many new oxomolybdenum(V) and dioxomolybdenum(VI) complexes have been synthesized with tri- and tetradentate Schiff bases derived by the condensation of salicylaldehyde, thiosalicylaldehyde,o-hydroxyacetophenone, 3-carboxysalicyclaldehyde or acetylacetone with aminoalcohols, polymethylenediamines ando-phenylenediamines. Mononuclear oxothiolato Schiff base complexes of molybdenum(V) have been prepared for the first time. Quadridentate Schiff bases derived from salicylaldehyde and substituted salicylaldehydes ando-phenylenediamine have also been successfully employed to isolate dioxomolybdenum(VI) complexes in the solid state, in which two oxygen atoms of the MoO2 group arecis- to each other, similar to the situation observed for other dioxomolybdenum(VI) complexes of salicylaldehyde-polymethylenediamine Schiff base ligands.Structures have been determined with the help of elemental analyses, magnetic susceptibilities, molar conductances, i.r., electronic and1H n.m.r. spectral data.For Part IX, K. Dey, R. K. Maiti and J. K. Bhar,Indian J. Chem., in press. 相似文献