Archive for May 19, 2016
S.A. Kras’ko, S.S. Zlotskii, V.P. Boyarskii
“Comparative Activity of Aryl, Alkyl, and Cycloalkyl Halides in the Suzuki Reaction Catalyzed with Acyclic Diaminocarbene Complex of Palladium”
Russ. J. Gen. Chem., 2016, 85(11), 2541-2546
Relative activity of halogenated arenes, alkanes, and alkanes in the Suzuki reaction catalyzed with acyclic diaminocarbene complex of palladium has been investigated. Under all the investigated conditions, 4-iodoanisole has been more active than the alkyl halides. The reaction with 4-methyl-1-(chloromethyl)benzene has afforded the target 4-methyl-1-(phenylmethyl)benzene along with significant amount of by-products; other alkyl and cycloalkyl halides do not participate into the cross-coupling reaction. Ethanol has been found the most suitable solvent for the reaction. The reaction in acetonitrile provides noticeable yield of the products only in the presence of polyethylene glycol and water.
D.N. Konshina, V.V. Open’ko, Z.A. Temerdashev, A.A. Gurinov, V.V. Konshin
“Synthesis of novel silica-gel-supported thiosemicarbazide and its properties for solid phase extraction of mercury”
Separation Sci. Tech., 2016, 51(7), 1103-1111
A new thiosemicarbazidе-modiﬁed silica gel (SG-THSC) sorbent was prepared. The sorbent was quantified by adsorption of mercury ions on silica gel, desorption and then spectrophotometry detection of mercury ions. The retention parameters (sample flow rate, eluent type, sample volume, presence of foreign ions, shaking time, sample flow rate and volume, eluent condition, interfering substances) were investigated. The quantitative recovery (>95%) of Hg(II) ions could be obtained by use of 5 mL of 6 mol L−1 HCl. The adsorption capacity of SG-THSC was found to be 98.3 mg g–1 at optimum pH. The maximum preconcentration factor was 400. The technique detection limit was 70 ng L–1, and the relative standard deviation was lower than 4.0% (n = 6). The studied sorbent was applied to preconcentrate the trace Hg(II) from the mineralised residues of fish and seawater samples.