Synthetic Route of 345637-71-0, A common heterocyclic compound, 345637-71-0, name is 2-(5-Methyl-3-(trifluoromethyl)-1H-pyrazol-1-yl)acetic acid, molecular formula is C7H7F3N2O2, 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) Preparation of 2-{1-[2-(5-methyl-3-trifluoromethyl-pyrazol-1-yl)-acetyl]piperidin-4-yl}-thiazole-4-carboxylic acid ethyl ester To a solution of (5-methyl-3-trifluoromethyl-pyrazol-1-yl)-acetic acid (9.1 g, 36.1 mmol) in DMF (100 mL) is added diisopropylethylamine (45 mL, 216 mmol), followed by O-(benzotriazol-1-yl)-N,N,N’,N’-tetramethyluronium tetrafluoroborate (15.5 g, 39.7 mmol). After stirring 15 min at RT, 2-piperidin-4-yl-thiazole-4-carboxylic acid ethyl ester hydrochloride (10 g, 36.1 mmol) is added to the reaction mixture. After stirring overnight at RT, solvent is evaporated and the resulting yellow oil is dissolved in ethylacetate (300 mL), washed with saturated aqueous sodium bicarbonate solution (300 mL), 1M HCl solution (300 mL), and brine (100 mL). The organic layer is dried over sodium sulfate, filtered, and evaporated under reduced pressure. The crude mixture is purified by column chromatography on silica gel (dichloromethane/methanol 10:1) to give 2-{1-[2-(5-methyl-3-trifluoromethyl-pyrazol-1-yl)acetyl]piperidin-4-yl}-thiazole-4-carboxylic acid ethyl ester. 1H-NMR (400 MHz, CDCl3): delta=1.40 (t, 3H), 1.70-1.85 (m, 2H), 2.16-2.30 (m, 2H), 2.32 (s, 3H), 2.79-2.89 (m, 1H), 3.22-3.43 (m, 1H), 4.03-4.12 (m, 1H), 4.42 (q, 3H), 4.54-4.69 (m, 1H), 4.93-5.08 (2d, 2H (diastereotopic)), 6.35 (s, 1H), 8.10 (br, 1H). MS: m/z=209 (M+1).
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; SYNGENTA PARTICIPATIONS AG; Umarye, Jayant; Berthon, Guillaume; Cederbaum, Fredrik Emil Malcolm; Luksch, Torsten; Lamberth, Clemens; Sulzer-Mosse, Sarah; Kanjilal, Pranab; Sonawane, Ravindra; US2014/243371; (2014); A1;,
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