These common heterocyclic compound, 455-75-4, name is Ethyl 3-amino-4-fluorobenzoate, 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. Formula: C9H10FNO2
To a stirred solution of [3-(1, 1-DIMETHYLETHYL)-1-ETHYL-4, 5-DIHYDRO-LH-PYRAZOLE-] 5-carboxylic acid (i. e. the product of Step D) (0.8 g, 4.1 mmol) in dichloromethane (5 mL) was added 1-propanephosphonic acid cyclic anhydride (50 wt % solution in ethyl acetate, 3.9 g, 6.14 mmol) followed by 4- (dimethylamino) pyridine [(0. 75] g, 6.14 mmol). After stirring for 1 h, ethyl [3-AMINO-4-FLUOROBENZOATE] (0.68 g, 3.7 mmol) was added, and the resulting solution was stirred at room temperature overnight. The solvent was removed in vacuo and partitioned between water (50 mL) and ethyl acetate (100 mL). The aqueous layer was extracted with ethyl acetate (30 mL). The organic layer was washed with aqueous saturated sodium bicarbonate (50 mL) and water (50 mL), and dried [(MGSO4).] The solvent was removed in vacuo to provide the title product, a compound of the present invention, as an oil (1.36 g). 1H NMR (CDC13): [B] 9.3 (s, 1H), 8.95 (d, 1H), 7.80 (m, 1H), 7.16 (t, 1H), 3.70 (t, 1H), 3.33 (dd, 1H), 3.18 (dq, 1H), 2.95 (dq, 1H), 2.83 (dd, 1H), 1.39 (t, 3H), 1.21 (t, 3H), 1.17 (s, 9H).
The synthetic route of Ethyl 3-amino-4-fluorobenzoate has been constantly updated, and we look forward to future research findings.
Reference:
Patent; E.I. DU PONT DE NEMOURS AND COMPANY; WO2004/35545; (2004); A2;,
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