Reference of 41680-34-6, A common heterocyclic compound, 41680-34-6, name is 3-Amino-1H-pyrazole-4-carboxylic acid, molecular formula is C4H5N3O2, 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.
A mixture of 5-amino-i H-pyrazole-4-carboxylic acid (807 mg, 6.35 mmol) and methyl 2,4- dioxopentanoate (i.83 g, i2.7 mmol) in acetic acid (4.9 ml, 86 mmol) was heated for i hat iioC in a microwave reactor. Upon cooling to room temperature, the reaction mixture waspoured into water and the resulting precipitate was filtered off. The residue was washed with methanol to give the title compound (6i 5 mg, 85% purity) together with unknown impurities.[C-MS (Method i): Rt = 0.62 mm; MS (ESIpos): m/z = 236 [M+H]1H-NMR (400 MHz, DMSO-d6) 6 [ppm]: i.906 (2.ii), 2.666 (i6.00), 2.855 (i.3i), 2.857 (i.32), 3.962 (2.ii), 4.003 (i5.5i), 7.570 (5.55), 8.583 (5.25), 8.753 (0.73).
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.
Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; EIS, Knut; ACKERMANN, Jens; WAGNER, Sarah; BUCHGRABER, Philipp; SUeLZLE, Detlev; HOLTON, Simon; BENDER, Eckhard; LI, Volkhart; LIU, Ningshu; SIEGEL, Franziska; LIENAU, Philip; BAIRLEIN, Michaela; VON NUSSBAUM, Franz; HERBERT,Simon; KOPPITZ, Marcus; (734 pag.)WO2016/177658; (2016); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics