With the rapid development and complex challenges of chemical substances, the synthesis of new drugs is usually one of the most effective ways to increase yield.832735-56-5, name is 4-Bromo-2-(difluoromethoxy)pyridine, molecular formula is C6H4BrF2NO, molecular weight is 224.0029, as common compound, the synthetic route is as follows.category: pyridine-derivatives
A mixture of C41 (120 mg, 0.467 mmol), C49 (105 mg, 0.469 mmol), tn’s(dibenzylideneacetone)dipalladium(0) (12.8 mg, 14.0 pmol), 4,5- bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos; 17.8 mg, 30.8 pmol), and cesium carbonate (608 mg, 1 .87 mmol) in 1 ,4-dioxane (5 mL) was stirred at 100 C for 16 hours. After cooling to room temperature, the reaction mixture was filtered, and the filtrate was concentrated in vacuo. The residue was purified using silica gel chromatography (Eluent: 20: 1 petroleum ether / ethyl acetate) to provide the product as a yellow oil. Yield: 50 mg, 0.17 mmol, 36%. 1 H NMR (400 MHz, CDCI3) delta 7.81 (d, J=5.9 Hz, 1 H), 7.42 (t, JHF=73.7 HZ, 1 H), 6.08 (dd, J=5.8, 2.1 Hz, 1 H), 5.75 (d, J=2.0 Hz, 1 H), 4.20-4.1 1 (m, 4H), 3.66 (dd, J=8.0, 5.5 Hz, 2H), 3.20-3.09 (m, 1 H), 2.71 (d, J=7.9 Hz, 2H), 1 .28 (t, J=7.1 Hz, 3H).
At the same time, in my other blogs, there are other synthetic methods of this type of compound,832735-56-5, 4-Bromo-2-(difluoromethoxy)pyridine, and friends who are interested can also refer to it.
Reference:
Patent; PFIZER INC.; ZHANG, Lei; BUTLER, Christopher Ryan; BECK, Elizabeth Mary; BRODNEY, Michael Aaron; BROWN, Matthew Frank; MCALLISTER, Laura Ann; LACHAPELLE, Erik Alphie; GILBERT, Adam Matthew; (170 pag.)WO2018/2760; (2018); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem