With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.1194-16-7,2,2-Dimethyltetrahydropyran-4-one,as a common compound, the synthetic route is as follows.
To a solution of 7,7-dimethyloxepan-4-one and 2,2-dimethyloxepan-4-one (2.6 g, 18.3 mmol) and pyrrolidine (85 mg, 1.2 mmol) in dimethyl sulfoxide (20 mL) was slowly added ethyl diazoacetate (1.39 g, 12.2 mmol). After addition, the reaction was stirred at 22 C for 16 h and poured into water (30 mL). The mixture was then extracted with ethyl acetate (3 x 30 mL).The combined organic layers were washed with water (2 x 30 mL) and brine (30 mL), dried over sodium sulfate and concentrated to dryness in vacuo. The residue was purified by column chromatography (silica gel, 100-200 mesh, 0 to 18% ethyl acetate in petroleum ether) to afford a mixture of three regio-isomers (900 mg, 20.6% yield) as yellow oil. The regio-isomers were separated by SFC to afford: Peak 1 (Rention time 3.31 min), ethyl 5,5-dimethyl-4,5,7,8-tetrahydro-1H-oxepino[4,5-c]pyrazole-3-carboxylate (200 mg): 1H MR (400 MHz, CDC13) delta 4.38 – 4.33 (m, 2H), 3.88 (t, J = 6.0 Hz, 2H), 3.11 (s, 2H), 2.97 (t, J= 6.00 Hz, 2H), 1.37 (t, J= 6.00 Hz, 2H), 1.21 (s, 6H) Peak 2 (Rention time 3.37 min), ethyl 7,7-dimethyl-4,5,7,8-tetrahydro-1H-oxepino[4,5-c]pyrazole-3-carboxylate (150 mg) as a yellow oil: NMR (400 MHz, CDC13) delta 4.39 – 4.34 (m, 2H), 3.92 – 3.87 (m, 2H), 3.08 – 3.03 (m, 2H), 2.98 (s, 2H), 1.38 (t, J= 6.0 Hz, 3H), 1.23 (s, 6H) Peak 3 (Rention time 6.30 min), ethyl 6,6-dimethyl-4,5,6,8-tetrahydro-1H-oxepino[3,4-c]pyrazole-3-carboxylate (150 mg) as a yellow oil: 1H MR (400 MHz, CDC13) delta 4.68 (s, 2H), 4.40 – 4.35 (m, 2H), 3.00 – 2.92 (m, 2H), 1.95 – 1.88 (m, 2H), 1.39 (t, J = 6.0 Hz, 3H), 1.33 (s, 6H). SFC conditions: Column: Chiralpak AD-3 150×4.6mm I D., 3um Mobile phase: A: C02 B: ethanol (0.05% DEA) Gradient: from 5% to 40% of B in 5 min and hold 40% for 2.5 min, then 5% of B for 2.5 min Flow rate: 2.5mL/min Column temp.: 35C Column: Chiralpak AY 150×4.6mm ID., 3um Mobile phase: A: C02 B: iso-propanol (0.05% DEA) Gradient: from 5% to 40% of B in 5 min and hold 40% for 2.5 min, then 5 for 2.5 min Flow rate: 2.5mL/min Column temp.: 35C, 1194-16-7
The synthetic route of 1194-16-7 has been constantly updated, and we look forward to future research findings.
Reference£º
Patent; GENENTECH, INC.; F. HOFFMANN-LA ROCHE AG; PATEL, Snahel; HAMILTON, Gregory; STIVALA, Craig; CHEN, Huifen; ZHAO, Guiling; (1236 pag.)WO2017/4500; (2017); A1;,
Tetrahydropyran – Wikipedia
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