Application of 14531-55-6, These common heterocyclic compound, 14531-55-6, name is 3,5-Dimethyl-4-nitro-1H-pyrazole, 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.
Step 1. Synthesis of 1-Benzyl-3,5-dimethyl-1H-pyrazol-4-amine (IA3a) To a solution of 3,5-dimethyl-4-nitropyrazole (IA1, 1.41 g, 10 mmol) in DMF (30 mL) were added benzyl bromide (IA2a, 2.05 g, 12 mmol) and Cs2CO3 (6.52 g, 20 mmol) and the mixture was allowed to stir at rt for 24 h. The reaction was quenched with water (50 mL) and the mixture was extracted with EtOAc. The organic phase was washed with water and brine, dried over anhydrous Na2SO4, and concentrated in vacuo. After purification by flash column chromatography (0-50% EtOAc/hexanes), 1-benzyl-3,5-dimethyl-4-nitro-1H-pyrazole was obtained as a white solid (1.39 g, 60%). 1H NMR (CDCl3, 600 MHz) delta 7.37-7.28 (m, 3H), 7.16-7.12 (m, 2H), 5.26 (s, 2H), 2.56 (s, 3H), 2.55 (s, 3H). HRMS (ESI+) calcd for C12H14N3O2 (M+H)+ 232.1081, found 232.1079.
The synthetic route of 14531-55-6 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; REGENTS OF THE UNIVERSITY OF MINNESOTA; Chen, Liqiang; Ai, Teng; (48 pag.)US2018/71258; (2018); A1;,
Pyrazole – Wikipedia,
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