Electric Literature of 1260243-04-6,Some common heterocyclic compound, 1260243-04-6, name is Ethyl 5-amino-1H-pyrazole-4-carboxylate, molecular formula is C6H9N3O2, 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.
General procedure: A mixture of ethyl-5-amino-1H-pyrazole-4-carboxylate 1 (1.0 mmol), an appropriate aldehyde 2 (1.0 mmol) and aterminal alkyne 3 (1.0 mmol) in acetic acid (5 mL) was stirred at 25 °C for 10 min. The mixture was then stirred at 60 °C under ultrasound using a laboratory ultrasonic bath SONOREX SUPER RK 510H model producing irradiationof 35 kHz for 30 min in the presence of air. The increase of bath temperature beyond 60 °C due to the prolonged ultrasound irradiation was controlled by adding cold water time to time. After completion of the reaction the mixture was cooled to room temperature, poured into ethyl acetate (25 mL) and washed with brine solution (2 x 15 mL) followed by 10percent NaHCO3 solution (2 x 15 mL). The organiclayer was collected, dried over anhydrous Na2SO4, filteredand concentrated under low vacuum. The residue isolatedwas purified by column chromatography over silica gel using3-8percent petroleum ether-EtOAc to give the desired product.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Ethyl 5-amino-1H-pyrazole-4-carboxylate, its application will become more common.
Reference:
Article; Suresha, Namburi; Durgaraoa, Bodapati Veera; Ratnakar; Kolli, Sunder Kumar; Ashfaq, Mohd Ashraf; Rao, Mandava V. Basaveswara; Pal, Manojit; Letters in drug design and discovery; vol. 14; 10; (2017); p. 1176 – 1183;,
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