With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.61995-20-8,Benzyl 3-oxopiperidine-1-carboxylate,as a common compound, the synthetic route is as follows.,61995-20-8
A mixture of benzyl 3-oxopiperidine-l-carboxylate (25 g, 0.107 mmol, 1.0 ep), ethyl cyanoacetate (14.54 g, 0.129 mmol, 1.2 eq), NH4OAc (2.09 g, 0.026 mmol, 0.25 eq) and acetic acid (5 mL) in toluene (250 mL) was refluxed at 130 C for 16 h. After the completion of reaction (TLC: Rf. 0.5 (30% ethyl acetate in hexane)), the reaction mixture was cooled to room temperature, quenched with a saturated aqueous solution of NaHC03 (500 mL) and extracted with EtOAc (2 x 300 mL). The combined organic layer was dried over Na2S04, filtered and concentrated under reduced pressure to afford crude product. The crude was purified by column chromatography (200-400 mesh silica-gel, eluent hexanes/EtOAc 90: 10 to 80:10,) to afford benzyl (?T)-3-(l-cyano-2-ethoxy-2- oxoethylidene)piperidine-l-carboxylate (24 g, yield: 68%) as a thick liquid. LCMS: 89%; *H NMR (400 MHz, DMSO-<) delta (ppm): 7.46 - 7.33 (m, 4H), 7.10 (d, / = 12.7 Hz, 1H), 5.19 - 5.15 (d, / = 13.4 Hz, 3H), 4.19 (dq, / = 14.2, 7.1 Hz, 2H), 3.59 - 3.50 (m, 2H), 2.10 (dt, / = 16.7, 6.3 Hz, 1H), 2.03 - 1.90 (m, 1H), 1.82 (d, / = 8.5 Hz, 2H), 1.22 (dq, / = 10.8, 6.1, 4.3 Hz, 4H). MS (ESI) m/z 329 [C18H20N2O4 + H] +
As the paragraph descriping shows that 61995-20-8 is playing an increasingly important role.
Reference：
Patent; AGENCY FOR SCIENCE, TECHNOLOGY AND RESEARCH; NACRO, Kassoum; (223 pag.)WO2018/21977; (2018); A1;,
Piperidine – Wikipedia
Piperidine | C5H11N – PubChem