5930-28-9Relevant articles and documents
Synthesis method of 2, 6-dichloro-4-aminophenol
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, (2021/06/12)
The invention discloses a synthesis method of 2, 6-dichloro-4-aminophenol, and belongs to the field of preparation of pesticide, medicine and dye intermediates, 2, 6-dichloro-4-aminophenol is obtained by adopting paranitroaniline as a raw material through the steps of chlorination, diazonium hydrolysis, hydrogenation and the like, methanol is adopted as a solvent for chlorination, filtrate can be repeatedly used, and the use of a large amount of acid water is reduced; toluene is selected as a solvent in diazotization, diazonium liquid is directly layered after being hydrolyzed, an organic layer is separated out, water vapor distillation is not needed, and the distillation risk and energy consumption are reduced; toluene is selected as a hydrogenation solvent, and an organic layer separated after the diazonium liquid is hydrolyzed is directly hydrogenated, so that the process flow is simplified.
Synthesis method of aminophenol
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Paragraph 0077-0138, (2020/07/13)
The invention provides a synthesis method of aminophenol. According to the method, by reacting nitrophenol with hydrogen under the conditions of an auxiliary agent and a solvent, an aminophenol product with high selectivity and yield can be prepared, the auxiliary agent can well control the reaction depth of nitrophenol and hydrogen, thereby inhibiting the side reaction, enhancing the purity of the final product, overcoming the problems of poor selectivity and high three-waste amount in the common hydrazine hydrate, sodium hydrosulfite and other reducing agents in the prior art, and having higher industrial application value.
Gold-Catalyzed Dearomative Spirocyclization of N-Aryl Alkynamides for the Synthesis of Spirolactams
Vacala, Taylor L.,Carlson, Paul R.,Arreola-Hester, Asa,Williams, Chloé G.,Makhoul, Evana W.,Vadola, Paul A.
, p. 1493 - 1501 (2018/02/10)
A catalytic redox-neutral method for the synthesis of spirolactams proceeding through the dearomative spirocyclization of N-aryl alkynamides is reported. In contrast to stoichiometric activating agents employed for related transformations, we show that the use of 5 mol % of Au(PPh3)Cl and AgOTf in dichloroethane at 50-80 °C leads to selective spirocyclization, furnishing the products in yields of 35-87%. The substrate scope of the reaction is good, with both electron-donating and electron-withdrawing groups being tolerated around the arene ring, as well as substitution at the amide nitrogen. The identity of the para-alkoxy group on the arene ring is key to achieving selectivity for spirocyclization over alternative mechanistic pathways. While the presence of a para-methoxy group leads to trace amounts of the desired spirolactams, the para-tert-butoxy or para-hydroxy substrate analogues furnish the spirolactams in good yield with high selectivity.