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Hamideh Ahankar Yavar Ahmadi 《Phosphorus, sulfur, and silicon and the related elements》2014,189(7-8):914-923
AbstractReactions of N-isocyaniminotriphenylphosphorane with cyclopentanone in the presence of an E-cinnamic acid derivative and a primary amine proceeds smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeds smoothly and cleanly under mild conditions and no side reactions were observed. 相似文献
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Vahideh Mahdavi Hamideh Hamidi 《International journal of environmental analytical chemistry》2013,93(14):1342-1351
ABSTRACTA fast, selective and sensitive reversed-phased liquid chromatography coupled to ion-trap mass spectrometry has been developed to elucidate and confirm the diazinon metabolites with a wide range of polarity in the rice plant samples. Sample extraction and purification were performed with a QuEChERS-based (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure. To boost all metabolism sensitivities, all rice extracts were concentrated under vacuum to near dryness and taken up into initial mobile phase. Careful optimisation of the LC–MS/MS parameters were achieved in order to attain a fast separation with the best sensitivity. The detection was carried out on an ion-trap mass spectrometer by electrospray ionisation in positive ion mode (ESI+) with multiple reaction monitoring. 相似文献
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Ebrahim Mollashahi Hamideh Gholami Mehrnoosh Kangani Mojtaba Lashkari Malek Taher Maghsoodlou 《Heteroatom Chemistry》2015,26(5):322-328
A green and efficient procedure for the synthesis of α‐aminophosphonates has been developed in water as a green and nonhazardous solvent, from condensation between aromatic aldehydes, aniline, and triphenyl phosphite at 80°C. This methodology has a number of advantages including clean reaction conditions, easy work‐up, and environmentally friendly. 相似文献
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We have prepared a fiber for solid-phase microextraction of organochlorine pesticides. A graphene-polyaniline composite was electrochemically deposited on a platinum fiber by exploiting the unique properties of polyaniline and graphene. The modified fiber displays thermal stability up to 320 °C and can be used more than 70 times. It possesses high extraction efficiency due to the high specific surface of graphene. The Pt fiber was used for the extraction and subsequent GC determination of the pesticides heptachlor, aldrin, endrin and p,p’-DDT in aqueous samples. The effects of extraction time, extraction temperature, stirring rate, salinity and headspace volume were optimized. Calibration plots are linear (with an R2 of 0.990) in the 0.2 to 250 μg L–1 concentration range, and the limits of detection are below 11 ng L–1 (at an S/N of 3). The relative standard deviations for three replicate measurements with a single fiber were <11.0 %. The recovery of the pesticides from spiked seawater samples ranged from 81 % to 112 %. Figure
The graphene–polyaniline (G/PANI) nanocomposite was prepared by simultaneous electropolymerization of G–aniline and used as a new coating for SPME of organochlorine pesticides as model compounds. The large delocalized π-electron system of G and high extraction capability of PANI caused to produce an efficient and sensitive sorbent for SPME 相似文献
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以淀粉溶液为催化剂锅三组分法合成四氢苯并[b]吡喃和3,4-二氢吡喃并[c]苯并吡喃衍生物简 总被引:2,自引:0,他引:2
Nourallah Hazeri Malek Taher Maghsoodlou Fatemeh Mir Mehrnoosh Kangani Hamideh Saravani Ebrahim Molashahi 《催化学报》2014,35(3):391-395
Tetrahydrobenzo[b]pyran and 3,4-dihydropyrano[c]chromene derivatives were synthesized via a one-pot three-component condensation of aromatic aldehydes with malononitrile and dimedone or 4-hydroxycoumarin in excellent yields in the presence of starch solution as a highly efficient homogenous catalyst. The use of a nontoxic and biodegradable catalyst, simple work-up procedure, and short reaction time are advantages of this method. 相似文献
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Mahnaz Farahi Bahador Karami Iman Sedighimehr Hamideh Mohamadi Tanuraghaj 《中国化学快报》2014,25(12):1580-1582
An efficient three-component synthesis of 6-amino-4-aryl-5-cyano-3-metriyl-1-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles via a reaction between 3-methyl-1-phenyl-2-pyrazolin-5-one,aromatic aldehydes and malononitrile using tungstate sulfuric acid as a catalyst was described.Mild conditions,good to excellent yields,easily available catalyst and easy work-up are the key features of this method. 相似文献