نتایج جستجو برای: preparation of phenols

تعداد نتایج: 21170811  

Journal: :Talanta 2011
Amjad H El-Sheikh Abdullah M Alzawahreh Jamal A Sweileh

Simultaneous preconcentration of phenol, 2-chlorophenol, 3-chlorophenol, 4-chlorophenol, 2-nitrophenol, 4-nitrophenol, and 2,4-dinitrophenol was improved by using olive wood (OW) washed with ethanol then pyrolyzed at 200°C as preconcentrating sorbent. Various OW sorbents were prepared by either washing OW (with ethanol, ether, dichloromethane, tetrahydrofuran or n-hexane); or by pyrolysis (at 1...

امجد, لیلا, رنجبر, منیره, محمدی, مهرنوش,

Production of heavy metals by human activity is caused soil contaminations. The polyamines are used to reduction of heavy metal effects. In this study, the effects of lead and spermidine on Salvia officinalis L. were tested. A factorial experiment was conducted in a completely randomized design with three replications. Lead nitrate at concentrations of 0, 125, 250 and 1000 micro molar and sperm...

Journal: :Chemical science 2013
Thanh Truong Olafs Daugulis

Two reactions of phenols with arynes have been developed. If LiTMP base is employed, arynes generated from aryl chlorides react with phenols to form helicenes. o-Arylation of phenols can be achieved by employing tBuONa base in the presence of AgOAc. Direct arylation of binol was achieved leading to the shortest pathway to o,o'-diarylbinols.

Journal: :Chemical communications 2013
Wei Zeng Wanqing Wu Huanfeng Jiang Liangbin Huang Yadong Sun Zhengwang Chen Xianwei Li

Regioselective synthesis of polysubstituted benzofurans using a copper catalyst and molecular oxygen from phenols and alkynes in a one-pot procedure has been reported. The transformation consists of a sequential nucleophilic addition of phenols to alkynes and oxidative cyclization. A wide variety of phenols and alkynes can be used in the same manner.

Trimethylsilylation of a variety of alcohols and phenols, in the presence of silica chloride, using hexamethyldisilazane (HMDS) in solution and under solvent-free conditions is reported. Trimethylsilyl ethers were formed in excellent yields both for aliphatic alcohols and phenols without having an electron-withdrawing group. In addition, SiO2-Cl can be recovered and reused after drying.

Journal: :Journal of colloid and interface science 2003
Walton J Cabrera Marcela Urzúa Hernán E Ríos

The effect of phenols containing different electron-withdrawing substituents on the potentiometric responses of several liquid PVC membranes containing the complex trioctylmethylammonium-nitrate, TOMA(+)NO(3)(-), is analyzed. The results make it possible to separate these phenols into two groups; those phenols containing electron-releasing groups, which produce almost Nernstian slopes, and thos...

2017
Yajun Liu Shasha Liu Yan Xiao

Phenols and aryl thiols are fundamental building blocks in organic synthesis and final products with interesting biological activities. Over the past decades, substantial progress has been made in transition-metal-catalyzed coupling reactions, which resulted in the emergence of new methods for the synthesis of phenols and aryl thiols. Aryl halides have been extensively studied as substrates for...

Journal: :Journal of the American Chemical Society 2011

Journal: :Applied and environmental microbiology 2010
Ariane Bisaillon Réjean Beaudet François Lépine Eric Déziel Richard Villemur

Desulfitobacterium hafniense strain PCP-1 reductively dechlorinates pentachlorophenol (PCP) to 3-chlorophenol and a variety of halogenated aromatic compounds at the ortho, meta, and para positions. Several reductive dehalogenases (RDases) are thought to be involved in this cascade of dehalogenation. We partially purified a novel RDase involved in the dechlorination of highly chlorinated phenols...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید