In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 288-13-1 as follows. Quality Control of 1H-Pyrazole
Step 1: Preparation of 3-pyrazol-1-yl-pyridine To a solution of 3-bromopyridine (5 g, 0.031 mol) in 50 ml of acetonitrile were added pyrazole (2.6 g, 0.038 mol), Cs2CO3 (16.5 g, 0.050 mol), Cu2O (0.226 g, 0.0016 mol), and salicylaldoxime (0.867 g, 0.006 mol) under N2 atmosphere. The reaction mass was refluxed for 24 hrs at 80 C. The reaction mass was concentrated and the crude was purified by column chromatography using ethyl acetate and hexane (1:1) to afford the pyrazolyl pyridine as a dark brown liquid (2 g, 43%): 1H NMR (400 MHz, CDCl3) delta 8.99 (d, J=2.8 Hz, 1H), 8.48 (dd, J=4.8, 1.2 Hz, 1H), 8.11-8.08 (m, 1H), 7.99 (d, J=1.2 Hz, 1H), 7.78 (d, J=1.2 Hz, 1H), 7.38-7.35 (m, 1H), 6.53 (t, J=1.2 Hz, 1H); MS (m/z) 146 [M+1].
According to the analysis of related databases, 288-13-1, the application of this compound in the production field has become more and more popular.
Reference:
Patent; Dow AgroSciences LLC; Buysse, Ann M.; Niyaz, Noormohamed M.; Demeter, David A.; Zhang, Yu; Walsh, Martin J.; Kubota, Asako; Hunter, Ricky; Trullinger, Tony K.; Lowe, Christian T.; Knueppel, Daniel I.; Patny, Akshay; Garizi, Negar; LePlae, JR., Paul Renee; Wessels, Frank J.; Ross, JR., Ronald; DeAmicis, Carl; Borromeo, Peter; (118 pag.)US2016/60245; (2016); A1;,
Pyrazole – Wikipedia,
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