87-65-0Relevant articles and documents
Method for catalytically synthesizing dichlorophenol by adopting surfactant catalyst
-
Paragraph 0032-0033; 0040-0041, (2020/06/09)
The invention belongs to the field of chemical synthesis, and particularly relates to a method for dichlorinating a phenolic substance, which directionally and selectively catalyzes substitution of C-H at an ortho-position and a para-position of phenolic hydroxyl by Cl atoms. The dichlorination method comprises the following steps: adding concentrated hydrochloric acid into a reactor, then addinga catalyst and a phenolic reactant, heating in an oil bath under violent stirring, and then adding a H2O2 aqueous solution with the mass percent concentration of 30-60%, and reacting for 2-26 hours and then ending the reaction, collecting an organic phase, and diluting with acetonitrile to prepare a sample for analysis. According to the dichlorination method disclosed by the invention, water is used as a reaction medium, so that the use of a traditional VOC organic solvent and heavy metals is avoided, and the method is safer and more environment-friendly. Meanwhile, the reaction conditions aremild, the operation is simple and convenient, the product yield is high, and the atom economy is high.
Method for producing high purity 2, 4 - dichlorophenol
-
Paragraph 0107-0115, (2019/07/04)
The invention provides a method for producing high purity 2, 4 - dichlorophenol, including: (1) heating and melting the raw materials, the mixed catalyst is added in the raw material, wherein the feedstock is phenol, O-phenol or [...] in at least one of, the mixed catalyst is phenyl sulfide, mixture of ferric chloride and trifluoromethanesulfonic acid; (2) to maintain the temperature of the material is 40 - 100 °C, to the material to carry out chlorination chlorinating agent is filled in the catalytic reaction to obtain 2, 4 - dichlorophenol crude product, the chlorinating agent is chlorine or sulfuryl chloride in at least one of; (3) to said 2, 4 - dichlorophenol crude melt crystallization, to obtain 2, 4 - dichlorophenol product. In this invention the states the chlorizating agent can be a chloride, can also be chlorine, the two can achieve higher conversion rate of raw materials, the application in the catalytic chlorination reaction the crude product obtained without rectification, only through the melt crystallization to obtain the purity 99% of the 2, 4 - dichlorophenol product.
Electrochemical Hydroxylation of Arenes Catalyzed by a Keggin Polyoxometalate with a Cobalt(IV) Heteroatom
Khenkin, Alexander M.,Somekh, Miriam,Carmieli, Raanan,Neumann, Ronny
supporting information, p. 5403 - 5407 (2018/04/19)
The sustainable, selective direct hydroxylation of arenes, such as benzene to phenol, is an important research challenge. An electrocatalytic transformation using formic acid to oxidize benzene and its halogenated derivatives to selectively yield aryl formates, which are easily hydrolyzed by water to yield the corresponding phenols, is presented. The formylation reaction occurs on a Pt anode in the presence of [CoIIIW12O40]5? as a catalyst and lithium formate as an electrolyte via formation of a formyloxyl radical as the reactive species, which was trapped by a BMPO spin trap and identified by EPR. Hydrogen was formed at the Pt cathode. The sum transformation is ArH+H2O→ArOH+H2. Non-optimized reaction conditions showed a Faradaic efficiency of 75 % and selective formation of the mono-oxidized product in a 35 % yield. Decomposition of formic acid into CO2 and H2 is a side-reaction.