These common heterocyclic compound, 118430-73-2, name is 3-(tert-Butyl)-1-methyl-1H-pyrazol-5-amine, 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. 118430-73-2
Pyrazole 5 (673 mg, 4.4 mMol), diisopropylethylamine (684 mg, 5.3 mMol, 1.2 eq.), and DCM (9 mL) were cooled to -10 C. and phenyl chloroformate (750 mg, 4.8 mMol, 1.1 eq.) was added in a single portion. The solution was allowed to warm to 0 C. and stir for 30 min. The solution was partitioned between ether and aqueous sodium bicarbonate and the ether layer was washed with brine. The organic fraction was dried over anhydrous sodium sulfate and the solvent removed in vacuo and the residue purified using silica gel chromatography eluting with ethyl acetate (5%-50%)/hexane. Solvent removal afforded the product (6) as brittle foam (1.0 g, 3.9 mMol, 90% yield), which provided a single peak by LC-MS analysis (M+H=274.1). 1H NMR (400 MHz, CDCl3) delta: 7.4 (dd, J=8.0, 7.6 Hz, 2H), 7.25 (tt, J=7.6 Hz, 1H), 7.18 (d, J=8.0 Hz, 2H), 6.95 (brs, 1H), 6.15 (s, 1H), 3.79 (s, 3H), 1.29 (s, 9H).
Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 118430-73-2.