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51.
Nagarajan Amirtha Seshaiyer Viswanathan Ramachandran Ganesan 《Monatshefte für Chemie / Chemical Monthly》1984,115(1):35-43
The kinetics of the addition of iodine monochloride (ICl) to some vinyl compounds in nitrobenzene solvent was investigated. In all cases the reaction follows second order dependence on ICl and first order on the substrate, making the total order three. Rate constants were measured for each substrate at 20°, 30°, 40° and 50°C.Arrhenius plots were made from which activation energies were evaluated. Other kinetic and thermodynamic parameters are reported. A suitable mechanism is proposed for the reaction and based on this, the various parameters are discussed. Solvent effects are discussed and the data with nitrobenzene and acetic acid solvents are compared.
Kinetik und Mechanismus der Addition vonICl zu einigen Alkenen in Nitrobenzol als Lösungsmittel. Effekt der Polarität des Lösungsmittels
Zusammenfassung Die Kinetik der Addition von ICl zu einigen Vinylverbindungen in Nitrobenzol als Lösungsmittel wurde untersucht. In allen Fällen ist die Reaktion von zweiter Ordnung hinsichtlich ICl und von erster Ordnung hinsichtlich des Substrats, d. h. mit einer Gesamtordnung von drei. Geschwindigkeitskonstanten wurden für jedes Substrat bei 20°, 30°, 40° und 50°C gemessen. AusArrhenius-Diagrammen wurden Aktivierungsenergien ermittelt und auch andere kinetische und thermodynamische Parameter wurden bestimmt. Ein Mechanismus wird vorgeschlagen, wobei die verschiedenen Parameter diskutiert werden. Lösungsmitteleffekte werden ebenfalls diskutiert und die Daten mit Nitrobenzol und Essigsäure als Lösungsmittel miteinander verglichen.相似文献
52.
53.
K Nagarajan P Madhavan Pillai A Nagana Goud R K Shah 《Proceedings Mathematical Sciences》1977,86(1):25-39
Decomposition of the diazonium chloride from N-(o-aminobenzoyl)-N-methylbenzylamine led to the formation of 3-benzyl-3, 4-dihydrobenzo-triazin-4-one (8), N-benzoylbenzylamine (11), N-benzylphthalimidine (13) ando-diphenic acid N-methyl amide (14), the last one presumably through the intermediary, the expected dibenzazepinone 16. From the analogue, N-(o-aminobenzoyl)-4-methoxybenzyl amine (4), triazinone 10 and N-benzoyl-4-methoxybenzyl amine (12) were obtained. Application of Pschorr reaction to N-(o-aminobenzoyl)-N-methyl-β-(4-methoxyphenyl) ethyl amine (23) afforded 2-methoxy-7-methyl-5, 6, 7, 8- tetrahydrodibenzo (c, e) azocin-8-one (26), with an interesting conformation. From N-(o-aminophenylacetyl)-p-methoxyaniline were obtained under these conditions, indazole-3-carboxylic acidp-anisidide (35) and N-[2-(4-methoxyphenyl carbamoylmethyl) phenyl]-1-(p-methoxyphenyl) isatin-β-hydrazone (37). The structure of 37 was deduced from spectral data and hydrolysis to the acid 42. Diazotisation of N-(o-aminophenylacetyl)-1, 2, 3, 4-tetrahydroquinoline (47) led to the formation of tetrahydroquinoline (49) ando-hydroxyphenyl acetic acid (50) presumably through the salicylamide 48. A similar reaction on N-(o-aminophenylacetyl) tetrahydroisoquinoline (52) gave the benzofurandione hydrazone 55, besides tetrahydroisoquinoline. Oxindole 45 and benzofuranone 56 were likely precursors for 37 and 55 respectively. Salicylamides 5, 7, 24 and 34 were byproducts in the Pschorr reaction. 相似文献
54.
Sujata Patil R. Nagarajan L. C. Gupta C. Godart R. Vijayaraghavan B. D. Padalia 《Hyperfine Interactions》1988,42(1-4):1063-1066
The series Eu2M3Si5 (M=Ni, Cu, Pd, Rh) have been synthesised for the first time. The Ni, Cu, Pd systems form in U2Co3Si5 type structure.151Eu Mössbauer spectroscopy shows that Eu is in valence fluctuating (VF) state in Ni system, while in Cu and Pd systems it is in stable divalent state. These observations are further confirmed by magnetic susceptibility studies. The material Eu2Rh3Si5 shows two lines in the Mössbauer resonance, one of which shows VF behaviour. 相似文献
55.
The behaviour of the threshold anomaly for non-central potentials, which account for collective excitations in heavy-ion collisions, is investigated. It is shown that the non-central potentials should exhibit an energy dependence at energies in the vicinity of the Coulomb barrier. This energy dependence is, however, different from that of the elastic optical potential, occurring at lower energies. It if further shown that there are corrections to the traditional collective model such that, if the transition potential is expressed as the derivative of the optical potential, the corresponding deformation length will be complex and energy-dependent. Simple model calculations are presented. 相似文献
56.
57.
Vadapalli Chandrasekhar Kandasamy Gopal Loganathan Nagarajan Palani Sasikumar Pakkirisamy Thilagar 《Journal of Chemical Sciences》2006,118(6):455-462
Phosphonate ligands, [RPO3]2-, are extremely versatile in the assembly of multi-tin and multi-copper architectures. We have used organostannoxane cores
for supporting multi-ferrocene and multi-porphyrin peripheries. The copper-metalated multi-porphyrin compound is an excellent
reagent for facile cleavage of DNA, even in the absence of a co-oxidant. Reaction oft-BuPO3H2 with Cu(C104)2. 6H2O in the presence of 2-pyridylpyrazole (2-Pypz) leads to the synthesis of a decanuclear copper (II) assembly. 相似文献
58.
D. T. Adroja R. Nagarajan S. K. Malik B. D. Padalia R. Vijayaraghavan 《Hyperfine Interactions》1988,41(1):535-538
New ternary compounds having the formula EuTCu4 where T=Al, Pd and Ag have been synthesized. All these compounds are found to crystallize in the hexagonal CaCu5 type structure. Magnetization measurements reveal that these compounds are magnetically ordered with magnetic moments close to 7 μB. The Curie temperatures obtained from low field ac susceptibility measurements are 26K, 25K and 50K for T-Al, Pd and Ag respectively.151Eu Mössbauer studies at room temperature show a large negative isomer shift relative to SmF3. A hyperfine split pattern is observed at 4.2K in all these compounds, indicating that Eu ion is present in a divalent state and is magnetically ordered. 相似文献
59.
R. Nagarajan A. K. Grover S. K. Dhar P. L. Paulose V. Nagarajan E. V. Sampathkumaran 《Hyperfine Interactions》1988,42(1-4):1227-1230
151Eu Mössbauer studies have been made across the respective superconductive transition temperatures in two compounds, La1.7Eu0.1Sr0.2CuO4?y and EuBa2Cu3O7, having zero resistance state at 25K and 85K respectively. The151Eu isomer shift data establish that Eu ions are in trivalent state at all temperatures. The Mössbauer f-factor does not show any significant anomaly across the TC. 相似文献
60.
2-Dichloracetamido-1-methyl-5-nitroimidazole undergoes novel cycloaddition with diazomethane to form 5-dichloracetylimino-tetrahydroimidazopyrazoles via 2-dichloracetylimino-1,3-dimethyl-5-nitroimidazoline. 相似文献