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91.
The molecular–electronic structure of the metal phthalocyanines (Fe, Co, Ni and Cu) has been determined by the molecular orbital treatment. Coulomb integrals of the metal atom occurring in the secular determinants have been approximated equivalent to the valence state ionization energy (VSIE) of a metal orbital for a particular charge configuration. The calculated π-electron charge densities have been found to be higher on the nitrogen atoms as compared to the other atoms in the molecule. This is in agreement with the e.s.r. studies of the metal phthalocyanines. To test the correctness of the molecular orbital calculations, the π-π* transitions (14,000 cm?1 ? 30000 cm?1), d-d* transitions (20000 cm?1 ? 60000 cm?1) and charge transfer transitions (15000 cm ?1 ? 30000 cm?1) have been calculated in the metal phthalocyanine molecules. The calculated frequencies have been compared with the observed ones and found in fair agreement. 相似文献
92.
K. Laxmi Venkat Rao M. Prasada Rao B. Sethuram T. Navaneeth Rao 《Transition Metal Chemistry》1989,14(3):165-168
Summary Uncatalysed and OsVIII-catalysed oxidation of dimethyl sulphoxide (DMSO) by potassium ferrate [FeVI] has been studied in alkaline medium in the 9.8–11.9 pH range, in the presence of IO
4
–
as a stabilizing agent. The order in [FeVI] and [DMSO] was found to be unity for the uncatalysed reaction and zero and fractional respectively for the catalysed reaction. The [OsVIII] order was unity in the catalysed reaction. The rate of oxidation decreased with increase in pH and the order in [H+] was fractional for the uncatalysed oxidation. However in the catalysed oxidation, the rate at first decreased and then increased with increase in pH. The effect of changing [IO
4
–
] and [buffer] on the oxidation rate was negligible in both cases. Suitable mechanisms consistent with the observed kinetics have been proposed. 相似文献
93.
Regeneration of Carbonyl compounds from the corresponding thioketals in nitrogen heterocycles have been effected using Dowex 50W acidic catalyst in reasonable yields. 相似文献
94.
95.
Devi Jai Pachwania Sushila Kumar Deepak Jindal Deepak Kumar Jan Suraya Dash Ashutosh K. 《Research on Chemical Intermediates》2022,48(1):267-289
Research on Chemical Intermediates - Organotin(IV) complexes are gaining major attention as drug candidates, accordingly we have synthesized a cluster of novel diorganotin(IV) complexes R2SnClL... 相似文献
96.
97.
Laxmi Kathawate Yogesh Shinde Ravi Yadav Sunita Salunke-Gawali 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1003-1011
The reactions of 3-chloro-2-hydroxy-1,4-naphthoquinone; chlorolawsone with “Na” metal (ClLw-1), CH3COONa (ClLw-2), NaOH (ClLw-3), KOH (ClLw-4) and K2CO3 (ClLw-5) have been studied. Dark brown solids obtained for ClLw-1 to ClLw-5 are characterized by elemental analysis FTIR, 1HNMR, UV–Visible spectroscopy, thermogravimetric analysis and DSC studies. FTIR of ClLw-1 to ClLw-5 shows decrease in νC=O frequency after complexation of alkali metal ions and νOH of adsorbed as well as coordinated water molecules have been observed between 3,600 and 3,100 cm?1. The benzenoid protons C(5)H and C(8)H shows down field shift due to intermolecular hydrogen bonding interaction with neighboring molecules and upfield shift have been observed for C(6)H and C(7)H protons in ClLw-1 to ClLw-5 in 1HNMR spectra. Bathochromic shift ~2 to ~5 nm have been observed for band at 287 nm. The nature of pyrolytic decomposition in chlorolawsone anion in ClLw-1 to ClLw-5 has been observed to be “gradual-1–abrupt–gradual-2”. Phase transition occurred during gradual-1 pyrolytic decomposition of chlorolawsone anion in ClLw-1 to ClLw-4 has been studied by DSC. 相似文献
98.
Kang Tae Wook Park Young Ji Jeong Gyu Jin Kim Seo Young Lee Mi Jai Hwang Jonghee Kim Jin-Ho Bae Byungseo Kim Sun Woog 《Journal of Solid State Electrochemistry》2022,26(8):1687-1692
Journal of Solid State Electrochemistry - Because of some drawbacks of the organic electrolytes, such as high toxicity and flammability, inorganic electrolytes have attracted attention regarding... 相似文献
99.
Attempts to synthesise iso-cladospolide-B, cladospolide-B and cladospolide-C resulted in macrolides 1, 2 and 4 along with butenolide 3. Of the three stereogenic centres, the C-4/C-5 vic-diol was obtained from tartaric acid and d-glucose, while the C-11 stereocentre was created by Jacobsen’s method. 相似文献
100.
The design and synthesis of a new family of potentially pentadentate N3Se2 or N3Te2 type donors bearing a 2,6-disubstituted pyridine dicarboxamide moiety as the central fragment [-NH-C(O)-pyridine-C(O)-NH-] functionalized with chalcogen as additional donors in the appended arms of the pyridine ring through the alkyl spacers and their potential applications and reactivity toward d8 and d10 metal ions have been demonstrated. 相似文献