Synthetic Route of 399-94-0, A common heterocyclic compound, 399-94-0, name is 1-Bromo-2,5-difluorobenzene, molecular formula is C6H3BrF2, 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.
Method A:To a nitrogen degassed, light brown solution of 2-bromo-1,4-difluorobenzene (48.3 mL, 0.429 mol) in CH2Cl2 (500 mL) was added i-PrMgCl (2.0 M in THF, 205 mL, 0.41 mol) slowly while the internal temperature was maintained below -15 C. The resulting reaction mixture was aged for additional 30 min. In a separate 500-mL round bottom flask, the Weinreb amide 4 (50 g, 0.195 mol) was dissolved in CH2Cl2 (300 mL) and cooled to -15 C. The Weinreb amide solution was transferred to the above aryl Grignard solution via cannula over 1 h such that temperature was less than -15 C. The reaction mixture was allowed to warm to room temperature upon completion of addition and aged overnight. The reaction mixture was quenched into a 3-L round bottom flask containing 1.2 L of half-saturated aqueous NH4Cl via cannula. The pH of the solution was then adjusted to 7 with concentrated HCl. Upon separation of the layers, the organic layer was dried over MgSO4 in preparation for isolation.
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; Xu, Feng; Kim, Mary M.; Kohmura, Yoshinori; Sladicka, Tricia; Rosen, Jonathan D.; Zacuto, Michael J.; US2009/187028; (2009); A1;,
Bromide – Wikipedia,
bromide – Wiktionary