Electric Literature of 14521-80-3, Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 14521-80-3, name is 3-Bromo-1H-pyrazole, This compound has unique chemical properties. The synthetic route is as follows.
A solution of 3-bromopyrazole (1.00 g, 6.8 mmol) in ethyl ether (20 mL) was treated with 37% formaldehyde (0.3 mL, 4.0 mmol). The obtained solution was set aside at room temperature overnight. The volatiles were evaporated under reduced pressure. Toluene (5 mL) was added, and the evaporation was repeated. The obtained oil was triturated with ethyl ether (3 mL) to crystallize. The crystals were separated by decantation and dried to give 3-bromo-l- (hydroxymethyl)pyrazole (371 mg, 37%). A suspension of the obtained product in chloroform (5 mL) was treated with thionyl chloride (0.5 mL) and heated at reflux for 1 h. The volatiles were removed under reduced pressure to provide crude 3-bromo-l-(chloromethyl)pyrazole. A suspension of the unsubstituted triazinone from Example 38 (100 mg, 0.41 mmol) in DMF (3 mL) was treated with 60% NaH (18 mg, 0.45 mmol) followed by 3-bromo-l- (chloromethyl)pyrazole (82 mg, 0.49 mmol). After stirring for 1 h at room temperature, the solvent was evaporated under reduced pressure, and the residue was chromatographed (chloroform/ethyl acetate, 1 : 1). The obtained material was recrystallized from ethanol (5 mL) to give the desired product, 70 mg, MP: 180-1810C. 1H NMR (CDCl3) delta 2.03 (1 H, m), 2.19 (1 H, m), 2.35 (1 H, m), 2.53 (1 H, m), 3.70 (1 H, m), 3.91 (1 H, dt, J = 12.3 and 7.2 Hz), 5.61 (1 H, t, J = 6.0 Hz), 6.55 ( 1 H, d, J = 13.8 Hz), 6.60 (1 H, d, J = 13.5 Hz), 7.51 (1 H, s), 7.85 (1 H, s), 7.87 (1 H, s), and 8.77 (1 H, s).
The chemical industry reduces the impact on the environment during synthesis 3-Bromo-1H-pyrazole. I believe this compound will play a more active role in future production and life.
Reference:
Patent; CORTEX PHARMACEUTICALS, INC.; WO2008/85505; (2008); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics