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81.
The kinetics of the oxidation of 2-methyl cyclohexanone and cycloheptanone with Fe(CN)6
3− catalyzed by RhCl3 in alkaline medium was investigated at four temperatures. The rate follows direct proportionality with respect to lower concentrations
of hexacyanoferrate(III) ion, but tends to become zero order at higher concentrations of the oxidant, while the reaction shows
first-order kinetics with respect to hydroxide ion and cyclic ketone concentrations. The rate shows a peculiar nature with
respect to RhCl3 concentrations in that it increases with increase in catalyst at low catalyst concentrations but after reaching a maximum,
further increase in concentration retards the rate. An increase in the ionic strength of the medium increases the rate, while
increase in the Fe(CN)6
4− concentration decreases the rate. 相似文献
82.
83.
Pushyamitra MishraHardesh K. Maurya Brijesh KumarVishnu K. Tandon Vishnu Ji Ram 《Tetrahedron letters》2012,53(9):1056-1059
An efficient and concise one pot synthesis of highly functionalized thiophenes and pyranone fused thiophenes has been delineated through base induced ring transformation of suitably functionalized 2H-pyran-2-ones by ethyl thioglycolate by inter and intramolecular C-S and C-C bond formation. 相似文献
84.
Vishnu K. Tandon Anoop K. Awasthi Hardesh K. Maurya Pushyamitra Mishra 《Journal of heterocyclic chemistry》2012,49(2):424-427
Beckmann rearrangement of (E)‐4‐chromanone oxime, (E)‐5‐oximino‐3,4‐dihydro‐1(2H)‐benzoxepines, and (E)‐5‐oximino‐3,4‐dihydro‐1(2H)‐benzothiepine are catalyzed by InBr3 and AgOTf in refluxing acetonitrile resulting in the formation of pharmaceutically active heterocycles benzoxazepin‐4‐one, 5‐oxo‐benzoxazocines, and 5‐oxo‐benzothiazocine derivative, respectively, in excellent yield. J. Heterocyclic Chem., (2012). 相似文献
85.
86.
Potentiometric studies of the mixed ligand derivatives of 11-Th(IV)—DTPA chelate (whereDTPA=diethylene-triamine pentaacetic acid) with certain secondary ligands, such as lactic, mandelic and o-hydroxynaphthoic acids have been carried out. The pH-titrations of the reaction mixtures containing 111 molar ratio of metal ion toDTPA to secondary ligand have shown the formation of 111 ternary complexes at higher pH (8). The equilibrium constants of the resulting mixed complexes have been determined at 30±1°C and =0.1 (KNO3) and the order of stability in terms of secondary ligands has been found to be o-hydroxy naphthoic acids>mandelic acid>lactic acid. 相似文献
87.
11 and 12 molar reactions of dioxouranium(VI) acetate dihydrate with the monobasic bidentateSchiff bases,o-HOC6H4CH=NR oro-HOC10H6CH=NR (R=C2H5,n-C3H7,n-C4H9 or C6H5) and bibasic tridentateSchiff bases,o-HOC6H4CH=NR(OH) oro-HOC10H6CH=NR(OH) (R=–CH2CH(CH3)- or —CH2CH2CH2–) have been studied and derivates of the type UO2(OAc)2(SBH), UO2(OAc)2(SBH)2, UO2(OAc)2(SBH
2) and UO2(OAc)2(SBH
2)2 (whereSBH andSBH
2 represent monobasic bidentate and bibasic tridentateSchiff base molecules respectively) have been isolated. These have been characterized by elemental analysis, conductance measurements and IR spectral studies.
UO2 2+-Komplexe von Schiff-Basen. VII. Uranylacetat-Komplexe mit monobasischen zweizähnigen und bibasischen dreizähnigen Schiff-Basen
Zusammenfassung Es wurden in 1:1- und 1:2-molaren Reaktionen von UO2(OAc)2·2H2O mitSchiff-Basen (L) Komplexe des Typs UO2(OAc)2 L bzw. UO2(OAc)2 L 2 isoliert. Die Komplexe wurden mittels Elementaranalyse, Leitfähigkeitsmessungen und IR-Spektren untersucht.相似文献
88.
Synthetic, structural and biological aspects of trigonal-bipyramidal, Me2S(N—S)CI and octahedral, Me2Si(N—S)2 types of diorganosilicon(IV) complexes of heterocyclic benzothiazolines (N—SH) are described. The complexes were characterized by elemental analysis, molecular weight determination, conductance measurements and electronic, infrared, 1H and 13C NMR spectroscopic studies. Some ligands and their corresponding dimethylsilicon(IV) complexes have been tested for their effects on several pathogenic fungi and bacteria and found to be quite active in this respect. Antifertility activity in male mice of some representative ligands and their silicon complexes was also evaluated and discussed. 相似文献
89.
Some five- and six-coordinated di- and tri-n-butyl tin(IV) complexes of the type Bu2SnL, Bu2SnL2 and Bu3SnL (where L is the anion of a monofunctional bidentate or bifunctional tridentate Schiff base) have been synthesized and characterised on the basis of microanalyses, molecular weight determinations, IR, NMR (1H, 13C, 119Sn) and 119Sn Mössbauer spectroscopy. These complexes are highly active towards bacteria. 相似文献
90.