نتایج جستجو برای: chlorides
تعداد نتایج: 3219 فیلتر نتایج به سال:
An environmentally benign and practical preparation method for the Vilsmeier-Haack reagent (VH) has been developed by using phthaloyl dichloride with DMF in toluene or 2-chlorotoluene. Phthalic anhydride as the byproduct was recovered in high yield by simple filtration. Some aromatic acids have been transformed into the corresponding acid chlorides in good yields by employing the isolated VH. T...
The photosulfochlorination of n-tetradecane by sulfuryl chloride leads to a reaction mixture containing unreacted n-tetradecane, chloro n-tetradecanes and n-tetradecanesulfonyl chlorides. Direct and simultaneous GC analysis of the mixture of the sulfochlorinated and chlorinated isomers is followed by mass spectrometry identification of all the components either by electron impact (EI-MS) and by...
This paper presents the spatial and temporal mass concentration variations of major acidic species (chlorides, nitrates and sulphates) in high risk particle fraction PM2..5 in Zagreb air. The sampling was carried out at four measuring sites during the summer of 2002 (June – July) and winter 2002-2003 (November – January). The results show no significant differences in pollutant concentration le...
New cis monocyclic beta-lactams were synthesized by [2+2] Staudinger cycloaddition reactions of the imine (3,4-dimethoxybenzylidene)-(4-methoxyphenyl)-amine and ketenes derived from different acyl chlorides and Et3N. These monocyclic beta-lactams were then cleaved by ceric ammonium nitrate (CAN) to give NH-monocyclic beta-lactams, which in turn were converted to N-sulfonyl monocyclic beta-lacta...
A new [2.2]paracyclophane-based electron-rich and sterically bulky monophosphine ligand has been synthesized by an efficient and straightforward method. When combined with palladium, this ligand shows excellent performance in the Buchwald-Hartwig amination and Suzuki-Miyaura coupling reactions of various aryl chlorides. In both types of reactions, ortho-substituted, deactivated aryl chlorides a...
3-Sulfanyloxindoles were synthesised by triphenylphosphine-mediated transition-metal-free thiolation of oxindoles using sulfonyl chlorides as sulfenylation reagents. The above reaction was promoted by iodide anions, which was ascribed to the in situ conversion of sulfenyl chlorides into the more reactive sulfenyl iodides. Moreover, the thiolation of 3-aryloxindoles was facilitated by bases. The...
A highly efficient copper-catalyzed system using commercially available racemic 1,1′-binaphthyl-2,2′-diol (rac-BINOL) as the ligand was eveloped for amination of aryl halides and heteroaryl halides with alkyl amines and N H heterocycles. Good to high yields were obtained for aryl romides and heteroaryl chlorides. The commercially available rac-BINOL ligand with excellent stability and high effi...
Yttrium iron garnet powders have been synthesized by chemical coprecipitation using two different precursors, nitrates and chlorides, and by an oxides mixture route. It is shown that depending on the precursors and synthesis conditions used pure yttrium iron garnet powders can be obtained with a mono or multidomain magnetic behaviour. The yttrium iron garnet crystalline structure, as studied by...
The synthesis of the title compounds was carried out by reacting dicarboxylic acid chlorides with oximes in the presence of excess triethylamine. Disubstituted malonyl chlorides gave 2-alkenyl-4,4-dialkyl-3,5-isoxazolidinediones (8a-f) and 2,2'-ethylidene-bis[4,4-dialkyl-3,5-isoxazolidinedione]s (9a-f). Compounds 9 were formed from 8 and its N-unsubstituted 3,5-isoxazolidinedione decomposition ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید