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991.
Phenacyl bromides are used as a building blocks in synthetic organic chemistry, which serves as a key model for the development of various biologically important heterocyclic compounds and other industrially important scaffolds. This review covers recent synthetic advances in the preparation of heterocyclic compounds utilizing various phenacyl bromides. A wide range of five- and six-membered heterocyclic compounds as well as fused heterocyclic compounds were synthesized efficiently from the phenacyl bromide precursors through one-pot multicomponent reactions. 相似文献
992.
Zhang Q. Vickers M.E. Patel A. Whatmore R.W. 《Journal of Sol-Gel Science and Technology》1998,11(2):141-152
The formation and growth of polymeric particles during the hydrolysis and condensation of PbZr0.3Ti0.7 O3 (PZT 30/70) sol-gel precursor solutions have been investigated by using photon correlation spectroscopy (PCS), small angle X-ray scattering (SAXS) and by measuring their rheological properties. The measurements showed that the growth of the particles in the transition of PZT sol to gel followed a simple polymerisation process. Solution A (containing by-products) and Solution B (by-products removed) displayed a similar plot of logarithmic viscosity against logarithmic time, indicating that the particles in both solutions have similar structures after hydrolysis. The changes in viscosity and particle size with time were described by single logarithmic growth models. However, the increasing rate of logarithmic particle size in Solution B is higher than that in Solution A. A model for the form of the aggregates is discussed which is applicable to PZT organometal-particle aggregation process in systems with acetic acid as a modifier. 相似文献
993.
Veerababurao Kavala Siva Murru Bhisma K. Patel Gopal Das 《Journal of chemical crystallography》2007,37(8):527-535
Various multi carbon homologations of 9-phenyl-9H-xanthen-9-ol (1) were obtained through a C-C bond formation by reacting it with various enolisable ketones in the presence of 1,1′-(ethane-1,2-diyl)dipyridinium
bistribromide (EDPBT). All the ten derivatives along with the starting xanthen-9-ol have been characterized by single crystal
X-ray diffraction. They all form self-assembled superstructure in the solid state. The self-assembling patterns in these supramolecular
architectures were explained based on steric and electronic nature of the pendant arm.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
994.
Yogesh O. Bhola Bhavesh N. Socha Sachin B. Pandya Rahul P. Dubey Maheshkumar K. Patel 《Molecular Crystals and Liquid Crystals》2019,692(1):83-93
AbstractThe synthesis of the compound and its crystal structure having a monoclinic crystal system has been reported earlier. Optimized bond lengths and angles are showing good agreements with experimental data using DFT/B3LYP method. Energy of highest occupied molecular orbital and lowest unoccupied molecular orbital has been predicted to analyze the stabilities of compound. Crystal explorer 17.5 helps to visualize intermolecular interactions and its contributions to each interaction within molecule. The preeminence of dispersion energy component over the other components was established by interaction energy calculations and lattice energy framework analysis using same software. The molecular docking study was performed for molecule using AutoDock software. 相似文献
995.
Using pressure-jump, concentration-jump, and stopped-flow methods, we have studied the rate of dehydration (k–1) of carbonic acid as a function of temperature (0–40°C) and ionic strength (0.005–3M NaCl, 3M LiBr) in both H2O and D2O. A new design of pressure-jump cell with reliable temperature control, as well as improved sensitivity in the spectrophotometric detection for stopped flow, enabled k–1 values to be determined with an accuracy better than ±8%, based on a comparison of results obtained using five different techniques. The influence of ionic strength, temperature, and isotope effects are discussed. 相似文献
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