31037-02-2, These common heterocyclic compound, 31037-02-2, name is Ethyl 5-amino-1-methyl-1H-pyrazole-4-carboxylate, 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.
Preparation of ethyl 5- Fbis(tert-butoxycarbonyl)aminol-l -methyl- lH-pyrazole-4-carboxylateEthyl S-amino-l-methyl-lH-pyrazole^-carboxylate (4.7 g, 27.78) in dichloromethane (100 mL) was stirred under nitrogen in a 500 mL flask as di-tert-butyl dicarbonate (7.88 g, 36.11 mmol) was added followed by N,N-dimethylpyridin-4-amine (339 mg, 2.78 mmol). The solution was stirred for 16 h. An additonal 5 g of di-tert-butyl dicarbonate was added and the solution was stirred for an additional 2 h. Very little starting material remained at this point and the solvents were evaporated to give a residue that was purified using silica gel. Products were eluted with a gradient from 0-80 % ethyl acetate in hexane to yield 8.1 g (79%) of the title pure material.1H NMR (300 MHz, CD2C12-4) ? 7.85 (s, IH), 4.25 (q, 2H), 2.68 (s, 3H), 1.40 (s, 18H), 1.30 (t, 3H); ES-MS m/z 370.0 [M+H]+, LCMS RT (min) 3.17.
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 31037-02-2.