345-70-0Relevant articles and documents
Method for preparing symmetric diarylketone through catalytic oxidative carbonylation
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Paragraph 0023; 0024; 0025; 0026; 0028, (2019/03/08)
The invention discloses a method for preparing symmetric diarylketone of a formula (I) as shown in the description. The method comprises the following steps: mixing arylboronic acid (II) (Ar-B(OH)2 (II)), a palladium catalyst, a promoter and an organic solvent in a reactor, introducing air and CO having a volume ratio of (7-19):1, reacting under the conditions of a pressure of 1-6 atm and a temperature of 30-80 DEG C for 8-16 hours, and performing after-treatment on the reaction solution, thereby obtaining the product symmetric diarylketone. According to the method disclosed by the invention,the air directly serves as an oxidizing agent to replace the O2 to be applied to oxidative carbonylation of the arylboronic acid, and the ratio of the air to CO is beyond an explosion limit. Therefore, the catalytic system is safe and economic. The palladium catalyst is small in dosage and simple in separation and can be recycled for several times. The method disclosed by the invention is mild inreaction condition, excellent in substrate suitability and high in yield.
Temperature-controlled divergent synthesis of 4-alkoxy- or 4-alkenyl-chromanes via inverse electron-demand cycloaddition with in situ generated ortho-quinone methides
Tanaka, Kenta,Kishimoto, Mami,Hoshino, Yujiro,Honda, Kiyoshi
, p. 1841 - 1845 (2018/04/11)
The temperature-controlled divergent synthesis of 4-alkoxy- or 4-alkenyl-chromanes via inverse electron-demand cycloaddition with in situ generated ortho-quinone methides under identical reaction conditions except for thermal condition has been developed. At room temperature, the reaction generated 4-methoxychromanes, whereas the reaction performed at room temperature to 100 °C gave 4-alkenylchromanes. Trifluoromethanesulfonic acid was efficiently suitable in the reaction to give the 4-substituted chromanes. This divergent synthetic strategy exhibits a new method giving carbon–carbon or carbon–oxygen bond by controlling the reaction temperature.
Ligand-Free Palladium-Catalyzed Oxidative Carbonylative Homocoupling of Arylboron Reagents at Ambient Pressure
Zhao, Hongyuan,Han, Wei
supporting information, p. 4279 - 4283 (2016/09/14)
Arylboronic acids or potassium aryltrifluoroborates were readily oxidatively carbonylated to their corresponding diaryl ketones in high yields with high selectivities by ligand-free palladium-catalyzed homocoupling at atmospheric pressure. This novel method employs molecular oxygen or iodine as the oxidant and offers an attractive alternative to transition-metal-based oxidant systems.