327-51-5, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 327-51-5, name is 1,4-Dibromo-2,5-difluorobenzene belongs to bromides-buliding-blocks compound, it is a common compound, a new synthetic route is introduced below.
To a 1.0 M solution (tetrahydrofuran 1:1 toluene) of 2,2,6,6-tetramethylpiperidinylmagnesium chloride lithium chloride complex (200 cm3, 200 mmol) at -30 C. under inert atmosphere is added drop-wise a solution of 1,4-dibromo-2,5-difluoro-benzene (23.6 g, 86.8 mmol) in anhydrous tetrahydrofuran (150 cm3) over 30 minutes. After addition, the reaction mixture is stirred at -30 C. for 7 hours before ethyl chloroformate (22.6 g, 208 mmol) is added in one go. The mixture is then allowed to warm to 23 C. over 17 hours. Aqueous hydrochloric acid (1.0 M, 500 cm3) is added and the mixture stirred at 23 C. for 30 minutes. The product is extracted with diethyl ether (3*100 cm3). The combined organics are dried over anhydrous magnesium sulfate, filtered and the solvent removed in vacuo. The crude product is triturated with n-pentane to form a suspension. The product is filtered and washed with cold acetone, collected and dried under vacuum to give 2,5-dibromo-3,6-difluoro-terephthalic acid diethyl ester (12.0 g, 33%) as a white solid. 1H-NMR (300 MHz, CDCl3) 1.42 (6H, m, CH3), 4.49 (4H, q, CH3) 19F-NMR 108.72 (2F, s, CF).
The synthetic route of 1,4-Dibromo-2,5-difluorobenzene has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Merck Patent GmbH; D’LAVARI, Mansoor; MITCHELL, William; WANG, Changsheng; SPARROWE, David; (67 pag.)US2017/117477; (2017); A1;,
Bromide – Wikipedia,
bromide – Wiktionary