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61.
Saeed Kamali Hongxin Wang Devrani Mitra Hideaki Ogata Wolfgang Lubitz Brian C. Manor Thomas B. Rauchfuss Deborah Byrne Violaine Bonnefoy Francis E. Jenney Michael W. W. Adams Yoshitaka Yoda Ercan Alp Jiyong Zhao Stephen P. Cramer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(2):752-756
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Majid M. Heravi Fereshteh Hydarzadeh Yahya Farhangi Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1473-1475
Primary and secondary trimethylsilyl ethers are effeciently converted to the corresponding carbonyl compounds using HZSM-5 zeolite-supported CrO 3 under microwave irradiation in solventless system. 相似文献
65.
Hossein A. Oskooie Azam Ranjbaran Majid M. Heravi Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1711-1714
Reduction of aromatic nitro compounds to amine with hydroiodic acid was revisited. Under microwave irradiation on solid support the reduction proceeded efficiently and rapidly. 相似文献
66.
Majid M. Heravi Hossein A. Oskooie Pegah Kazemian Fatemeh Drikvand Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2341-2344
Cerium ammonium nitrate (CAN) adsorbed on HNO 3 /silica gel is a mild reagent for selective oxidation of benzylic alcohols to the corresponding aldehydes under microwave irradiation in solventless system. 相似文献
67.
Kaushik Sen Bhaskar Mondal Srimanta Pakhira Chandan Sahu Deepanwita Ghosh Abhijit K. Das 《Theoretical chemistry accounts》2013,132(8):1-17
The association reaction between silyl radical (SiH3) and H2O2 has been studied in detail using high-level composite ab initio CBS-QB3 and G4MP2 methods. The global hybrid meta-GGA M06 and M06-2X density functionals in conjunction with 6-311++G(d,p) basis set have also been applied. To understand the kinetics, variational transition-state theory calculation is performed on the first association step, and successive unimolecular reactions are subjected to Rice–Ramsperger–Kassel–Marcus calculations to predict the reaction rate constants and product branching ratios. The bimolecular rate constant for SiH3–H2O2 association in the temperature range 250–600 K, k(T) = 6.89 × 10?13 T ?0.163exp(?0.22/RT) cm3 molecule?1 s?1 agrees well with the current literature. The OH production channel, which was experimentally found to be a minor one, is confirmed by the rate constants and branching ratios. Also, the correlation between our theoretical work and experimental literature is established. The production of SiO via secondary reactions is calculated to be one of the major reaction channels from highly stabilized adducts. The H-loss pathway, i.e., SiH2(OH)2 + H, is the major decomposition channel followed by secondary dissociation leading to SiO. 相似文献
68.
Abhijit Chandra Roy V.S. Nisha Chetna Dhand Md. Azahar Ali B.D. Malhotra 《Analytica chimica acta》2013
We report results of the studies relating to the fabrication and characterization of a conducting polymer based molecularly imprinted para-nitrophenol (PNP) sensor. A water pollutant, para-nitrophenol is electrochemically imprinted with polyvinyl sulphonic acid (PVSA) doped polyaniline onto indium tin oxide (ITO) glass substrate. This PNP imprinted electrode (PNPI-PANI-PVSA/ITO) prepared via chronopotentiometric polymerization and over-oxidation is characterized by Fourier transform infra-red spectroscopy (FT-IR), UV–visible (UV–vis) spectroscopy, contact angle (CA), scanning electron microscopy (SEM), cyclic voltammetry (CV) and differential pulse voltammetry (DPV) studies. The response studies of PNPI-PANI-PVSA/ITO electrode carried out using DPV reveal a lower detection limit of 1 × 10−3 mM, improved sensitivity as 1.5 × 10−3 A mM−1 and stability of 45 days. The PNPI-PANI-PVSA/ITO electrode shows good precision with relative standard deviation of 2.1% and good reproducibility with standard deviation of 3.78%. 相似文献
69.
Aplysin (1), a marine sesquiterpene was isolated from ‘aplysia kurodai’ and its structure was ellucidated by Hirata-et-al1. They also reported the synthesis of racemic aplysin2. Their synthetic route involved cyclopentanone (2) as a well-characterized intermediate. We visualized the synthesis of cyclobutanone (3) and its subsequent conversion to (2) as an attractive alternative. But during our attempts to synthesize the said cyclobutanone, we have come across a very facile intramolecular ‘ene’ reaction between ketene and olefin. We report our unexpected observations in this communication. 相似文献
70.
Z-6-Heneicosen-11-one (1) and Z-1,6-Heneicosen-11-one (2) are the sex pheromones of the Douglas-Fir Tussock moth, ‘Orgyia Pseudo Sugata’, isolated1,2 in 1975 and 1978 respectively. In contrast with other lepidopterous pheromones, which are unsaturated C12-C14 primary alcohols or acetates, these were found to be C21 ketones. The Douglas-Fir Tussock moth is a severe defoliator of the Fir forest; consequently, considerable interest attends the synthesis of these two pheromones. A number of syntheses of these two pheromones have been reported3 amongst which is one of our synthesis using N,N-dimethyl acetone 4 hydrazone as key intermediate. 相似文献