Reference of 1073-39-8, A common heterocyclic compound, 1073-39-8, name is 3-Bromobicyclo[4.2.0]octa-1,3,5-triene, molecular formula is C8H7Br, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
A magnetic stir bar and 3.10 g of magnesium strip were added to the reactor.The vacuum was purged with nitrogen three times (to ensure the removal of oxygen in the system), and 6 mL of tetrahydrofuran and 0.010 g of iodine activated magnesium strip were added to the reactor under nitrogen protection.20 g of 4-bromobenzocyclobutene was diluted in 36 mL of tetrahydrofuran to obtain a mixed solution.A few drops of the mixed solution was added dropwise at room temperature, and the reaction was initiated by contact with magnesium strips and iodine. After the reaction of tetrahydrofuran was slightly refluxed, the mixed solution was slowly added dropwise, and the addition was completed in 2 hours.After the addition was completed, the system was transferred to a 70 C oil bath for 2 h. The temperature was lowered to room temperature under a nitrogen atmosphere, and 14 g of dimethylvinylchlorosilane was diluted in 30 mL of tetrahydrofuran to obtain a mixed solution.The mixture was slowly added dropwise to the human system, and the addition was completed in 2 hours. After the completion of the dropwise addition, the system was transferred to a 70 C oil bath, and the reaction was continued for 2.5 h to obtain an off-white slurry.Separation and purification: After the reaction is completed, the obtained off-white slurry is cooled to room temperature.The excess Grignard reagent was quenched by the addition of 3 mol/L of dilute hydrochloric acid (the amount of dilute hydrochloric acid added was allowed to react the remaining magnesium strips in the reaction).It was extracted with 25 mL of n-hexane, extracted three times, and the organic phases were combined. After washing with dilute hydrochloric acid, saturated aqueous sodium hydrogencarbonate solution and saturated aqueous sodium chloride solution,It was dried over anhydrous sodium sulfate for 5 h. Filtration and concentration of the filtrate on a rotary evaporator afforded a pale yellow liquid.The liquid was subjected to distillation under reduced pressure and a fraction having a temperature of 80 C was collected to obtain a colorless transparent liquid, which was a 4-dimethylvinylsilylbenzocyclobutene (4-DMVSBCB).
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; Southwest University of Science and Technology; Yang Junxiao; Wei Xuelian; Yin Qiang; Hu Huan; Li Xian; Fan Li; Ma Jiajun; (14 pag.)CN108503664; (2018); A;,
Bromide – Wikipedia,
bromide – Wiktionary