38254-49-8Relevant academic research and scientific papers
Oxidative bromination of alkenes mediated with nitrite in ionic liquids
Kuznetsova, Lidia I.,Kuznetsova, Nina I.,Zudin, Vladimir N.,Utkin, Viktor A.,Trebushat, Dmitry V.,Fedotov, Martin A.,Larina, Tatyana V.
, p. 1499 - 1506,8 (2014/11/08)
The oxidative bromination of C2-C8 alkenes with HBr-NaNO2-O2 in solutions of BMImBr, HMImBr or BMImBF 4 containing 16-28 wt% H2O was studied using volumetric method, GC-MS analysis, 14N NMR and UV-VIS spectroscopy. The optimal conditions to conduct the reaction at high selectivity for 1,2-dibromoalkanes in BMImBr were determined. The composition of ionic liquid affects the catalytic performance. Although in BMImBF4 the reaction runs with equal rate as in bromide ionic liquid, the fraction of bromohydrin in the reaction products increases to 20 %. Generated from NaNO2, NOx operated as a catalyst in the oxidation of Br- and was oxidized to catalytically inert NO3 - anions when complete conversion of HBr was attained. Graphical Abstract: Oxidative bromination of alkenes [Figure not available: see fulltext.]
Solvent Effects on the Rate of Heterolysis of t-Butyl Chloride, Bromide, Iodide, and 2,4-Dinitrophenolate
Mitsuhashi, Tsutomu,Hirota, Hiroshi,Yamamoto, Gaku
, p. 824 - 830 (2007/10/02)
Rates of heterolytic decompositions of t-butyl chloride, bromide, iodide, and 2,4-dinitrophenolate have been measured by an NMR method in eight deuterated or undeuterated polar solvents; methanol-d4, ethanol-d6, dimethyl-d6 sulfoxide, N,N-dimethylformamide-d7, acetonitrile-d3, pyridine, nitrobenzene, and acetone-d6.The observed solvent effect is discussed on the basis of cation and anion solvation.With t-butyl halides, the anion solvation due to hydrogen bonding by protic solvents drastically decreases on increasing the radius of halide ions, and thus the differential solvation transferred from anion-solvating methanol to cation-solvating dimethyl sulfoxide is dramatically reversed on going from the chloride to the iodide (kMe2SO-d6/kmethanol-d4 at 60 deg C: t-BuCl, 5E-2; t-BuBr, 6E-1; t-BuI, 7).The 2,4-dinitrophenolate behaves like the iodide.Complicated products are obtained in the decomposition of t-butyl bromide in dimethyl sulfoxide; however, a mechanism involving a bimolecular decomposition process of the bromide is ruled out.During the decomposition od t-butyl iodide in dimethyl sulfoxide, an intermediate salt t-butoxydimethylsulfonium iodide has been detected.The salt decomposes to isobutene, but the process is much slower than the heterolytic decomposition of t-butyl iodide itself at ambient temperature.
