A new synthetic route of Ethyl 4-iodo-1H-pyrazole-5-carboxylate

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.

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 179692-08-1, name is Ethyl 4-iodo-1H-pyrazole-5-carboxylate, A new synthetic method of this compound is introduced below., Product Details of 179692-08-1

To a solution of ethyl 4-iodo-1H-pyrazol-3-formate (4.2 g, 15.8 mmol, 1.0 eq.) and potassium carbonate (4.37 g, 31.6 mmol, 2.0 eq.) in acetonitrile (45 mL) was added p-methoxybenzyl chloride (3.09 g, 19.7 mmol, 1.25 eq.) under stirring at room temperature. The reaction liquid was protected with nitrogen gas and stirred overnight at 60C. The reaction liquid was cooled to room temperature and insoluble substances were filtered. The filter cake was washed with ethyl acetate. The filtrate was concentrated in vacuo and separated by column chromatography on silica gel column to give ethyl 4-iodo-1-(4-methoxybenzyl)-1H-pyrazol-5-formate (C1, 1.94 g, 32% yield) and ethyl 4-iodo-1-(4-methoxybenzyl)-1H-pyrazol-3-formate (C2, 2.90 g, 47% yield). C1: 1H NMR (400MHz, CDCl3) delta 7.61 (s, 1H), 7.21 (d, J = 8.4 Hz, 2H), 6.82 (d, J = 8.4 Hz, 2H), 5.70 (s, 2H), 4.37 (q, J = 7.2 Hz, 2H), 3.77 (s, 3H), 1.40 (t, J = 7.2Hz, 3H). m/z=409[M+Na]+. C2: 1H NMR (400MHz, CDCl3) delta 7.36 (s, 1H), 7.22 (d, J = 8.8 Hz, 2H), 6.90 (d, J = 8.4 Hz, 2H), 5.31 (s, 2H), 4.44 (q, J = 7.2 Hz, 2H), 3.81 (s, 3H), 1.43 (t, J = 7.2Hz, 3H). m/z=409[M+Na]+.

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.