Adding a certain compound to certain chemical reactions, such as: 51437-00-4, name is 4-Bromo-1-fluoro-2-methylbenzene, belongs to bromides-buliding-blocks compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 51437-00-4, Quality Control of 4-Bromo-1-fluoro-2-methylbenzene
Step 1. 5-Bromo-2-fluoro-3-methylbenzaldehyde: To a stirred solution of di- isopropyl amine (4.01 g, 39.88 mmol) in THF (20 mL) was added n-butyl lithium (1.6 M in hexane) (19.9 mL, 31.91 mmol) at -78 C slowly dropwise over the period of 10 min, the reaction mixture was stirred at -78C for 30 min. A solution of 4-bromo-l-fluoro-2- methylbenzene (5.0 g, 26.6 mmol) in THF (30.0 mL) was added at -78C, and the reaction mixture was stirred for lh at the same temperature. DMF (5.0 mL) was added and stirred at – 78C for another 30 min. The reaction was monitored by TLC; then the reaction mixture was quenched with IN HC1 solution (aq) at 0C. The aqueous layer was extracted with diethyl ether, washed with water and saturated brine solution. The combined organic layer was dried over anhydrous Na2S04 and concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (Si02, 100-200 mesh; eluting with 5% ethyl acetate/ pet ether) to afford the title compound as a white solid (3.6 g, 64 ); mp 48- 50C: ]H NMR (400 MHz, CDC13) delta 8.33 (s, 1H), 8.22 (s, 1H), 7.67 (s, 1H), 7.60 (s, 1H), 6.75 (dd, J = 17.6, 10.8 Hz, 1H), 5.92 (dd, J = 17.6, 10.8 Hz, 1H), 5.52 (d, J = 17.6 Hz, 1H), 2.21 (s, 3H); ESIMS m/z 211.35 ([M-H]”).
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 4-Bromo-1-fluoro-2-methylbenzene, and friends who are interested can also refer to it.
Reference:
Patent; DOW AGROSCIENCES LLC; LO, William C.; HUNTER, James E.; WATSON, Gerald B.; PATNY, Akshay; IYER, Pravin S.; BORUWA, Joshodeep; WO2014/100163; (2014); A1;,
Bromide – Wikipedia,
bromide – Wiktionary