1123-63-3Relevant articles and documents
Lau,Kestner
, p. 4426 (1968)
Application of two morphologies of Mn2O3for efficient catalyticortho-methylation of 4-chlorophenol
Gui, Wenying,Liu, Xiaofei,Wang, Zhenlu,Zhang, Chunlei,Zhang, Hongqiang,Zhang, Li,Zhu, Wanchun
, p. 20836 - 20849 (2021/07/01)
Vapor phaseortho-methylation of 4-chlorophenol with methanol was studied over Mn2O3catalyst with two kinds of morphologies. Here, Mn2O3was prepared by a precipitation and hydrothermal method, and showed the morphology of nanoparticles and nanowires, respectively. XRD characterization and BET results showed that, with the increase of calcination temperature, Mn2O3had a higher crystallinity and a smaller specific surface area. N2adsorption/desorption and TPD measurements indicated that Mn2O3nanowires possessed larger external surface areas and more abundant acid and base sites. Simultaneously, in the fixed bed reactor, methanol was used as the methylation reagent for theortho-methylation reaction of 4-chlorophenol. XRD, XPS, TG-MS and other characterizations made it clear that methanol reduced 4-chlorophenol and its methide, which were the main side-reactions. And Mn3+was reduced to Mn2+under the reaction conditions. Changing the carrier gas N2to a H2/Ar mixture further verified that the hydrogen generated by the decomposition of methanol was not the reason for dechlorination of 4-chlorophenol compounds. Here we summarized the progress of 4-chlorophenol methylation based on the methylation of phenol. Also, we proposed a mechanism of the 4-chlorophenol dechlorination effect which was similar to the Meerwein-Ponndorf-Verley-type (MPV) reaction. The crystal phase and carbon deposition were investigated in different reaction periods by XRD and TG-DTA. The reaction conditions for the two kinds of morphologies of the Mn2O3catalyst such as calcination temperature, reaction temperature, phenol-methanol ratio and reaction space velocity were optimized.
Effects of Halogen Substiution on Reactions of o-Quinol Acetates with Isopropylmagnesium Bromide and Diisopropylmagnesium. Competition between Unimolecular Decomposition and Bimolecular Reactions of Radical Anions
Miller, Bernard,Haggerty, John G.
, p. 174 - 179 (2007/10/02)
When a single methyl substituent at C-2 or C-4 of an o-quinol acetate (1) is replaced by a halogen atom, a greatly decreased yield of the corresponding 3-isopropylphenol is obtained from reaction of 1 with isopropylmagnesium bromide.Replacement of a second methyl group by halogen results in a marked increase in the yield of the 3-isopropylphenol.Essentially identical product distributions are obtained from reactions of halogenated o-quinol acetates with concentrated and dilute Grignard solutions and with diisopropylmagnesium, in contrast to reactions with halogen-free o-quinol acetates.Reactions with hexadeuterioisopropylmagnesium bromide gave reduction products bearing increasing percentages of deuterium at C-3 as the number of bromines on the rings of the ω-quinol acetates increased.These data are consistent with reactions of halogenated o-quinol acetates, in contrast to those of halogen-free analogues, proceeding solely by SET processes.The reactions of halogen-stabilized radical anions with isopropyl radicals compete with decomposition of radical anions to phenoxy radicals.
Reactivity Dependence on the Crystalline State. Reaction of Gaseous Chlorine on Solid Phenols
Vicens, Jacques,Perrin, Robert,Bavoux, Claude
, p. 71 - 74 (2007/10/02)
Reaction of gaseous chlorine on powders of 3,5-dichlorophenol (A), 2,6-dimethylphenol (B), 1 : 1 molecular compound between A and B (C) and the mixture of equimolar amounts of powders of A and B (D) is studied under different experimental conditions.When the molecules are engaged in the compound C, the reactivity of the least reactive molecules (A) decreases while the reactivity of the most reactive molecules (B) increases.An attempt is made to interpret the results from the crystalline structures of A, B and C.
