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71.
72.
Planar nickel(II) complexes involving N‐(2‐Hydroxyethyl)‐N‐methyldithiocarbamate, such as [NiX(nmedtc)(PPh3)] (X = Cl, NCS; PPh3 = triphenylphosphine), and [Ni(nmedtc)(P‐P)]ClO4(P‐P = 1,1‐bis(diphenylphosphino)methane(dppm); 1,3‐bis(diphenylphosphino)propane (1,3‐dppp); 1,4‐bis(diphenylphosphino)butane(1,4‐dppb) have been synthesized. The complexes have been characterized by elemental analyses, IR and electronic spectroscopies. The increased νC–N value in all the complexes is due to the mesomeric drift of electrons from the dithiocarbamate ligands to the metal atom. Single crystal X‐ray structure of [Ni(nmedtc)(1,3‐dppp)]ClO4·H2O is reported. In the present 1,3‐dppp chelate, the P–Ni–P angle is higher than that found in 1,2‐bis(diphenylphosphino)ethane‐nickel chelates and lower than 1,4‐bis(diphenylphosphino)butane‐nickel chelates, as a result of presence of the flexible propyl back bone connecting the two phosphorus atoms of the complex. 相似文献
73.
The replacement of liquid acid catalyst by solid acids for the Friedel‐Crafts reaction of aromatic alkylation is a challenging task. Mixed oxide possessing spinel structures were found to catalyze the Friedel‐Craft benzylation of arenes. It was found that the reaction was very fast at 80 °C, hence the reaction was studied with respect to more substrate. The significant point was even at this temperature monobenzylation, with the para isomer predominating, was achieved. Mixed oxides were prepared by co‐precipitation method and were characterized by XRD technique. 相似文献
74.
75.
M. Damodara Poojary S. P. Sudhakara Rao H. Manohar 《Journal of Chemical Sciences》1983,92(4-5):485-495
X-ray structural studies on metal complexes with nucleotides and with pyridoxalamino acid Schiff bases are briefly reviewed.
The results with ternary metal nucleotide complexes show that the oxopurine nucleotides coordinate to the metal ion through
the N(7) atoms of the bases incis position. The relevance of this mode of binding is discussed in terms of the possible mechanism of action of the novel platinum
drugs. On the basis of the studies on metal pyridoxal-amino acid Schiff base complexes, the variations in stereochemistry
of the ligands in different metal complexes have been related to the catalytic activity of various metal ions in pyridoxal-catalyzed
nonenzymatic reactions. 相似文献
76.
Ling-Ju Chang Manohar V. Kulkarni Chung-Ming Sun 《Central European Journal of Chemistry》2005,3(2):288-294
Liquid phase combinatorial synthesis using a soluble polyethylene glycol (PEG) polymer support and commercially available
3-nitro-4-fluoro benzoic acid is carried out in order to create a molecular library of trisubstituted benzimidazoles. The
PEG-ester conjugate of 3-nitro-4-fluoro benzoic acid is subjected to ipso-fluoro displacement by various primary amines. The nitro group is reduced under neutral conditions using excess zinc and
ammonium chloride, producing the polymer-boundo-phenylene diamines. Reaction of the diamines with different aldehydes results in cyclisation to benzimidazoles. The polymer
support is cleaved releasing the desired products in high yields and purity. All reactions are performed at room temperature.
相似文献
77.
R. K. Dutta R. N. Acharya V. Chakravortty A. G. C. Nair A. V. R. Reddy S. N. Chintalapudi S. B. Manohar 《Journal of Radioanalytical and Nuclear Chemistry》1998,232(1-2):91-96
Hot electron injection into aqueous electrolyte solution was studied with electrochemiluminescence and electron paramagnetic
resonance (EPR) methods. Both methods provide further indirect support for the previously proposed hot electron emission mechanisms
from thin insulating film-coated electrodes to aqueous electrolyte solution. The results do not rule out the possibility of
hydrated electron being as a cathodic intermediate in the reduction reactions at cathodically pulse-polarized thin insulating
film-coated electrodes. However, no direct evidence for electrochemical generation of hydrated electrons could be obtained
with EPR, only spin-trapping experiments could give information about the primary cathodic steps. 相似文献
78.
S. Samundeeswari Lokesh A. Shastri Bahubali M. Chougala Megharaja Holiyachi Manohar V. Kulkarni 《Tetrahedron letters》2017,58(20):1996-1998
Oxime ethers obtained from benzil monooxime and 4-bromomethy coumarins have undergone an unusual transformation into coumarin-4-carboxamides. Structures of the products have been supported by X-ray studies and robustness of the reaction has been investigated for a variety of substituent. 相似文献
79.
G. Pathak R. Katiyar K. Agrahari A. Srivastava R. Dabrowski K. Garbat R. Manohar 《Opto-Electronics Review》2018,26(1):11-18
In the present work TiO2 nanoparticles (NPs) have been dispersed into three different nematic liquid crystals (2020, 1823A and 1550C) in different concentration. The value of the birefringence (Δn) has been calculated by the transmitted intensity method at a 632.8 nm wavelength. NLC 2020 used in the present study is a high birefringent material (Δn = 0.44), NLC 1550C is a low birefringent material (Δn = 0.067) and NLC 1823A is a mid birefringent material (Δn = 0.14). An increased value of birefringence has been found after dispersion of TiO2 NPs in all three NLCs but this increment depends upon the concentration of the dopant material, temperature range and chemical character of the mixtures. It is suggested that this LC materials can be applicable in making of phase shifters, compensators and many more photonic devices. 相似文献
80.