Some common heterocyclic compound, 78703-53-4, name is 1,3-Dimethyl-1H-pyrazole-4-carboxylic acid, molecular formula is C6H8N2O2, 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. Computed Properties of C6H8N2O2
To a suspension of 6-(2-amino-5-chlorothiazol-4-yl)-3,4-dihydroquinolin-2(1H)-one hydrochloride (1.501 g, 0.611 mmol) and 1,3-dimethyl-1H-pyrazole-4-carboxylic acid (0.943 g, 0.67 mmol), and pyridine (2.23 mL, 27.52 mmol) in acetonitrile (60 mL) in a sealed tube was added propylphosphonic anhydride solution (50 wt % in ethyl acetate, 9.10 mL, 15.29 mmol). The sealed tube was heated to 100 C. for 24 hours and precipitation was observed. After cooling, the precipates were collected by filtration washed with 1:1 cold acetonitrile/water to give a beige solid product. The resulting filtrate was partitioned between EtOAc (50 mL) and 50 mL of water. Several extraction with EtOAc (4*25 mL) were made. The combined organic layers were washed with saturated brine, dried over anhydrous sodium sulfate and then concentrated in vacou. The residue was dried loaded onto silica and purified by silica gel column chromatography using 95:5 dichloromethane/methanol to give combined 1,3-dimethyl-N-(4-(2-oxo-1,2,3,4-tetrahydroquinolin-6-yl)thiazol-2-yl)-1H-pyrazole-4-carboxamide (1.04 g, 46%). 1H NMR (400 MHz, DMSO-d): delta 12.16 (bs, 1H), 10.18 (s, 1H), 8.55 (s, 1H), 7.73 (bs, 1H), 7.68 (dd, 1H, J=8.0, 2.0 Hz), 7.44 (s, 1H), 6.89 (d, 1H, J=8.0 Hz), delta, 3.82 (s, 3H), 2.93 (m, 2H) 2.48 (partial masked under d-DMSO, m, 2H), 2.39 (s, 3H). MS (ESI): Calcd. for C18H17N5O2S: 367, found 368 (M+1)+.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 78703-53-4, its application will become more common.