Reference of 139308-52-4,Some common heterocyclic compound, 139308-52-4, name is Ethyl 3-bromo-1-methyl-1H-pyrazole-4-carboxylate, molecular formula is C7H9BrN2O2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
[0941] to a solution of compound 163c (2.6 g, 11.16 mmol) in MeOH (10 ml) and H2O (10 ml) was added LiOH.H2O (2.34 g, 55.80 mmol). The mixture was stirred at 25 C for 12h. The reaction mixture was concentrated and added 20 ml of water and the mixture was extracted with mtbe (20 ml x 2), the aqueous layer was acidified by in HCl to ph ~ 2-3 at 0 C, and extracted with EtOAc (30 ml x 2), the organic phase was dried over Na2SO4 and concentrated to give a residue. Compound 163f (2.2 g, yield: 96.16%) was obtained as a gray solid, which was used for next step directly. 1H NMR (400mhz, DMSO-d6) delta 12.55 (br s, 1h), 8.24 (s, 1h), 3.81 (s, 3h).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Ethyl 3-bromo-1-methyl-1H-pyrazole-4-carboxylate, its application will become more common.