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991.
Ying‐Fang Ting Chihliang Chang Raju Jannapu Reddy Dr. Dhananjay R. Magar Kwunmin Chen Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(23):7030-7038
Practical and convenient synthetic routes have been developed for the synthesis of a new class of pyrrolidinyl–camphor derivatives ( 7 a–h ). These novel compounds were screened as catalysts for the direct Michael addition of symmetrical α,α‐disubstituted aldehydes to β‐nitroalkenes. When this asymmetric transformation was catalyzed by organocatalyst 7 f , the desired Michael adducts were obtained in high chemical yields, with high to excellent stereoselectivities (up to 98:2 diastereomeric ratio (d.r.) and 99 % enantiomeric excess (ee)). The scope of the catalytic system was expanded to encompass various aldehydes and ketones as the donor sources. The synthetic application was demonstrated by the synthesis of a tetrasubstituted‐cyclohexane derivative from (S)‐citronellal, with high stereoselectivity. 相似文献
992.
Optical absorption spectrum of Co2+ doped rubidium zinc sulphate hexahydrate has been investigated both at room and at liquid nitrogen temperatures. The gross features of the observed spectrum are characteristic of octahedral symmetry associated with spin-orbit interaction. The interelectronic repulsion (B, C), crystal field (Dq) and spin-orbit () parameters which give a good fit to the observed band positions areB = 860 cm–1,C = 3870 cm–,Dq = 980 cm–1,= 500 cm–1. The non-ligand bands observed in the spectrum are attributed to vibrational modes of water molecule.The authors are thankful to the Council of Scientific and Industrial Research, New Delhi (India) for financial support. 相似文献
993.
The perturbation approach of Barker and Henderson (1967, 1968) has been applied to a microemulsion obeying triangular well
potential as a perturbative attractive tail over the Percus-Yevick (PY) hard sphere model by calculating the Rayleigh ratio,R
90, under the mean spherical approximations. The results are in better agreement with experimental values.
Presented at the 70th Indian Science Congress, Tirupathi, January 3–8, 1983. 相似文献
994.
Rao RM Reddy UC Alinakhi Mulakayala N Alvala M Arunasree MK Poondra RR Iqbal J Pal M 《Organic & biomolecular chemistry》2011,9(10):3808-3816
A new one-pot synthesis of 2-(hetero)aryl indoles via sequential C-C coupling followed by C-Si bond cleavage and a subsequent tandem C-C/C-N bond forming reaction is described. A variety of functionalized indole derivatives were prepared by conducting this four step reaction under Pd/C-Cu catalysis. The methodology involved coupling of (trimethylsilyl)acetylene with iodoarenes in the presence of 10% Pd/C-CuI-PPh(3) and triethylamine in MeOH, followed by treating the reaction mixture with K(2)CO(3) in aqueous MeOH, and finally coupling with o-iodoanilides. The single crystal X-ray data of a synthesized indole derivative is presented. Application of the methodology, in vitro pharmacological properties of the synthesized compound, along with a docking study is described. 相似文献
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We prepared two heterooligomeric arrays based on free base/metalloporphyrins at axial positions and a metalloid phthalocyanine as a basal scaffolding unit by using the axial‐bonding capabilities as well as the known oxophilicity of dihydroxytin(IV) phthalocyanine. Both heterotrimers were completely characterized by elemental analysis, MALDI‐TOF MS, and 1H NMR (one‐ and two‐dimensional), UV/Vis, and fluorescence spectroscopy as well as cyclic voltammetry. The ground‐state properties indicate that there is minimal π–π interaction between the macrocyclic units. The excited‐state properties show that there is electronic energy transfer competing with photoinduced electron transfer from the singlet state of the axial porphyrin to the central metalloid phthalocyanine and a photoinduced electron transfer from the ground state of the axial porphyrin to the singlet state of the central metalloid phthalocyanine. 相似文献
1000.
P. Muralidhar Reddy Adapa V. S. S. Prasad Vadde Ravinder 《Transition Metal Chemistry》2007,32(4):507-513
Macrocyclic CuII compounds of the type Cu(L4)Cl2 (where L4 = N4 or N2O2 donor macrocyclic ligand) have been synthesized by treating the corresponding macrocycles with copper chloride in methanol.
These compounds were characterized with the help of elemental analysis, i.r., mass, ESR, electronic spectra, conductance,
magnetic and thermal studies. Distorted octahedral geometry has been proposed for all of these compounds. These compounds
were found to be efficient in the catalytic oxidation of ascorbic acid and the percentage yields of oxidation products were
determined spectrophotometrically. The biological activities of these compounds have been tested against gram +ve and gram
−ve bacteria and found to be more active when compared with commercially available antibacterials like streptomycin and ampicillin. 相似文献