General Description
Suzuki coupling reaction of 2-chloro-1,3-dimethylbenzene with arylboronic acids has been investigated. 2-Chloro-1,3-dimethylbenzene undergoes palladium-catalyzed cyanation reaction to afford 2,6-dimethyl benzonitrile.
Synthesis
In a 1 L four-neck flask, 110.8 g of phenyl 2,6-dimethyl chloroformate (cas:876-99-3) was slowly added dropwise to the reaction system, followed by 110.8 g of anhydrous aluminum trichloride. The reaction system was warmed up to 80 °C and then 554 g (3.0 mol) of phenyl 2,6-dimethyl chloroformate was added. During the addition, the reaction was exothermic and the temperature of the system was gradually increased to 100~110 °C. The reaction temperature was maintained at 100~110°C, and the holding time was continued for 3.0 hours after the addition was completed. Samples were taken and analyzed during the reaction, and when the remaining amount of raw material was 15~17%, the target products 2,6-dimethylchlorobenzene and 2-chlorotoluene were generated in 40% each. After the reaction was completed, the vacuum of the system was adjusted to 20~25 mbar, and the fractions with boiling points of 80~85 °C were collected. Finally, 185 g of 2,6-dimethylchlorobenzene liquid product was obtained, which was analyzed by gas chromatography (GC) with 99.0% purity and 43.8% yield.
