Application of 1280210-79-8, A common heterocyclic compound, 1280210-79-8, name is tert-Butyl 4,6-dihydropyrrolo[3,4-c]pyrazole-5(2H)-carboxylate, molecular formula is C10H15N3O2, 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.
To a stirred solution of feri-butyl 2,6-dihydropyriOlo[3,4-c]pyrazole-5(4H)- carboxylate (Step A of Intermediate 7) (35 g, 167 mmol) in DMF (500 mL) at 0 C under N2 was added sodium hexamethyldisilazide in THF (351 mL, 351 mmol) and the mixture was stirred at 0 C for 30 min. Isobutylene oxide (74.3 mL, 836 mmol) was then slowly added. The solution was stirred at 0C for 0.5 h and then stirred at room temperature for 1 h. The solution was heated to 80C for 100 min in a microwave oven, cooled to room temperature and evapoarted under vacuum. The residue was purified by column chromatography on silica gel, eluting with a gradient of 0% to 6% CH2Cl2 MeOH (containing 10% NH4OH) to give a mixture of two regioisomers. The mixture of two regioisomers A and B was resolved by chromatography on a ChiralPak AD-H column eluting with 4-40% MeOH/C02 to give isomer A as the faster eluting isomer and isomer B as the slower eluting isomer. NMR (500 MHz, CD3OD) for isomer B: 57.42 (d, 1H); 4.42 (s, 2H); 4.41 (s, 2H); 4.07 (s, 2H); 1.51 (d, 9H); 1.16 (s, 6H). LC-MS: 226.27 (M+l -56).The desired isomer B was treated with 1 : 1 TF A/CH2CI2 for 1 h to give the title compound. NMR (500 MHz, CD3OD): 67.55 (s, 1H); 4.43 (s, 2H); 4.39 (s, 2H); 4.10 (s, 2H); 1.17 (s, 6H). LC-MS: 182.31 (M+l).
The synthetic route of 1280210-79-8 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; MERCK SHARP & DOHME CORP.; HICKS, Jacqueline, D.; BIFTU, Tesfaye; CHEN, Ping; QIAN, Xiaoxia; WILKENING, Robert, R.; WO2011/146358; (2011); A1;,
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