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.
Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 348-57-2, name is 1-Bromo-2,4-difluorobenzene, A new synthetic method of this compound is introduced below., Recommanded Product: 1-Bromo-2,4-difluorobenzene
Method A: A suspension of Mg turnings (3.47 g, 143 mmol) in THF (250 mL) was heated to 35 °C under nitrogen. A portion of 1-bromo-2,4-difluorobenzene (1 mL, 8.85 mmol) was added to the reactor, and the resulting mixture was heated at 35 °C for 30 mm to initiate thereaction. The reaction mixture was cooled to 30 °C, and the remainder of 1-bromo-2,4- difluorobenzene (16.4 mL, 145.15 mmol) was added to the reactor at 28?32 °C over 30 mm. The reaction was stirred at 30 °C for 2 h, at which point complete consumption of Mg was observed. The reaction was cooled to less than 0 °C, and a solution of ethyl 2-(5-(4- cyanophenoxy)pyridin-2-yl)-2,2-difluoroacetate (III) (35 g, 110 mmol) in THF (100 mL) wasadded at less than 5 °C over 30 mm. The reaction was stirred at 0 °C for 1 h and quenched into a 2 N HC1 solution (150 mL) at less than 10 °C (pH = 1?2). The reaction was stirred at 20 °C for 18 h, at which point HPLC analysis indicated that there was still about 10percent of hemiketal intermediate (ha) remaining. It was further stirred at 30 °C for 5 h, at which point HPLC analysis indicated that the hemiketal (ha) intermediate was fully consumed. The layerswere separated, and the aqueous layer was extracted with EtOAc (100 mL). The combined organic layers were washed with a sat. NaHCO3 solution (100 mL), dried over anhydrous Na2SO4, filtered, and concentrated to give a light tan solid (45.6 g). The solid was dissolved in EtOAc (60 mL) at 60 °C, and heptane (100 mL) was added. The mixture was seeded and stirred at 20 °C for 18 h to afford a suspension. The suspension was filtered and the solid was dried to afford the desired product as a white solid (25.5 g). The filtrate was concentrated andrecrystallized from MTBE (50 mL) and heptane (100 mL) to give a light brown solid (14.1 g)after drying, affording a combined yield of 90percent. ?H NMR (400 MHz, CDC13) 8.37 (d, J =2.7 Hz, 1H), 8.08 (td, J = 8.4, 6.4 Hz, 1H), 7.87 (d, J = 8.6 Hz, 1H), 7.75 ? 7.66 (m, 2H), 7.54(dd, J= 8.6, 2.8 Hz, 1H), 7.17?7.08 (m, 2H), 7.01 (dddd, J= 8.6, 7.6, 2.5, 0.9 Hz, 1H), 6.84 (ddd, J= 11.0, 8.6, 2.4 Hz, 1H); ESIMS m/z 387.0 ([M+Hj).
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; VIAMET PHARMACEUTICALS, INC.; YANG, Qiang; HAO, Yan; RYAN, Sarah; WHITEKER, Gregory; (26 pag.)WO2017/87643; (2017); A1;,
Bromide – Wikipedia,
bromide – Wiktionary