Reference of 1260243-04-6, A common heterocyclic compound, 1260243-04-6, name is Ethyl 5-amino-1H-pyrazole-4-carboxylate, molecular formula is C6H9N3O2, 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.
To a solution of ethyl 5-amino-lH-pyrazole-4-carboxylate (3.0 g, 19.3 mmol) in acetic acid (40 mL) and ethanol (10 mL) was added 1,1,3,3-tetramethoxypropane (3.48 g, 21.4 mmol). The reaction mixture was stirred at 90 ¡ãC overnight and cooled down to room temperature and then concentrated in vacuo. The residue was diluted with ethyl acetate (100 mL) and washed with saturated NaHC03aqueous solution (20 mL) and then dried over anhydrous Na2S04, filtered and concentrated in vacuo. The residue was purified by a silica gel column chromatography (DCM/EA (v/v) = 6/1) to give the title compound as a light yellow solid (3.2 g, 85percent).LC-MS (ESI, pos. ion) m/z: 192.3 [M+H]+; H NMR (600 MHz, CDC1 ): delta (ppm) 8.81 (m, 1H), 8.78 (m, 1H), 8.61 (s, 1H), 7.04 (dd, J = 6.9, 4.1 Hz, 1H), 4.47 (q, J= 7.1 Hz, 2H), 1.44 (t, J = 7.1 Hz, 3H).
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.