Electric Literature of 399-94-0, These common heterocyclic compound, 399-94-0, name is 1-Bromo-2,5-difluorobenzene, 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.
In a 3000 ml three-necked flask, a magnesium shavings (26.4 g, 1.1 mmol) and a solution of 2,5-difluorobromobenzene (2,5-difluorobromobenzene 200 g, 1.036mol) in tetrahydrofuran (1500 mL) were added dropwise. After completion, the whole temperature control (water bath) is reacted at 35-45 C; then, it is naturally cooled to 25 C, the ice water bath is cooled, and a solution of N-BOC pyrrolidone (150 g, 810 mmol) in tetrahydrofuran (300 ml) is added dropwise. After the addition is completed, the reaction is carried out for 2 h at room temperature; after the reaction of N-BOC-pyrrolidone is observed by TLC (RhoEpsilon/EpsilonAlpha = 2), the reaction is started with dilute hydrochloric acid (2N), and the pH is adjusted to 2-3; EA extraction, combined organic phase, washed with saturated brine, dried, evaporated to remove organic solvent, then added to the mixture of n-heptane 600ml, add 20g of activated carbon decolorization, heated reflux, hot filtered, solid precipitation, cooling to about 20 C, suction filtration The filter cake was washed with n-hexane and dried to give 158 g of the compound of formula (1) as a white solid (yield: 65.3%).
The synthetic route of 399-94-0 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Shanghai Xinkai Chemical Technology Co., Ltd.; Zhang Yichao; Dong Jinpeng; Li Xia; Gu Xuexin; (19 pag.)CN108101820; (2018); A;,
Bromide – Wikipedia,
bromide – Wiktionary