These common heterocyclic compound, 706819-66-1, name is 2-Bromo-1-(1-methyl-1H-pyrazol-4-yl)ethanone, its 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. Safety of 2-Bromo-1-(1-methyl-1H-pyrazol-4-yl)ethanone
2-Bromo-1 -(1 -methyl-1 H-pyrazol-4-yl)-ethanone (CAS 706819-66-1) (820 mg; 4.04 mmol) was added to a mixture of intermediate 2 (1 g; 3.36 mmol) and K2C03 (930 mg; 6.73 mmol) in DMF (20 mL). The reaction mixture was heated at 65C for 18 hours. The reaction mixture was cooled to room temperature, poured onto water and extracted with EtOAc. The organic layer was decanted, washed with brine, dried over MgS04, filtered and evaporated to dryness. The residue was purified by chromatography over silica gel (irregular SiOH 40g; mobile phase: 95% DCM, 5% MeOH, 0.5% NH4OH). The pure fractions were collected and evaporated to dryness, yielding 345 mg (25%) of intermediate 3. 1H NMR (500 MHz, DMSO-d6) delta 9.78 (s, 1 H), 9.27 (s, 1 H), 9.09 (s, 1 H), 8.71 (s, 1 H), 8.31 (s, H), 7.01 (t, J = 7.88 Hz, 1 H), 3.79 – 4.05 (m, 9H); MS (ESI+) m/z (%) (r.t. 2.34) 400 (100) [M+H]+, 799 (95) [2M+H]+ (method B1 ). MP. : 224C (Kofler).
The synthetic route of 2-Bromo-1-(1-methyl-1H-pyrazol-4-yl)ethanone has been constantly updated, and we look forward to future research findings.
Reference:
Patent; ASTEX THERAPEUTICS LIMITED; SAXTY, Gordon; HAMLETT, Christopher Charles Frederick; BERDINI, Valerio; MURRAY, Christoper William; ANGIBAUD, Patrick Rene; QUEROLLE, Olivier Alexis Georges; PONCELET, Virginie Sophie; WO2013/179033; (2013); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics