Synthetic Route of 609-12-1, A common heterocyclic compound, 609-12-1, name is Ethyl 2-bromo-3-methylbutanoate, molecular formula is C7H13BrO2, 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.
General procedure: General Method 4C: N-Alkylation of 2-pyridinonederivatives with the appropriate 2-bromo-or 2-chloropropanoic ester derivativesin the presence of sodium hydride/lithium bromide Under argon and at 0 C, 1.25eq. of sodium hydride (60% in mineral oil) were added to a solution of 1.0 eq.of the appropriate 2-pyridinone derivative in dimethylformamide (5-10 ml/mmol),and the mixture was stirred at 0 C for 10-20 min. 2.0 eq. of lithium bromidewere then added, the reaction mixture was stirred at RT for 15 min, 1.25 eq. ofthe appropriate 2-bromo- or 2-chloropropanoic ester derivative were added andthe mixture was stirred at 65 C. After removal of the DMF and addition ofwater/ethyl acetate and phase separation, the organic phase was washed withwater, dried (sodium sulphate), filtered and concentrated under reducedpressure. The crude product was then purified either by flash chromatography(silica gel 60, mobile phase: cyclohexane/ethyl acetate mixtures or dichloromethane/methanol mixtures) or bypreparative HPLC (Reprosil C18, water/acetonitrile gradient or water/methanolgradient).500 mg (2.9 mmol) of 4-bromopyridin-2(1H)-one and 841mg (4.02 mmol) of ethyl 2-bromo-3-methylbutanoate (racemate) in the presence of1.15 eq. of sodium hydride and 2.3 eq. of lithium bromide were reactedaccording to General Method 4C. Yield: 260 mg (purity92%, 28% of theory)
The synthetic route of 609-12-1 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Bayer Pharma Aktiengesellschaft; Rurik, Jujane; Hilliswe, Alexander; Strassburke, Yulia; Hidemeyer, Stefan; Smith, Martina Victoria; Schlemmer, Karl-Heinz; Terstigen, Adrian; Buchmuller, Anya; Gerdes, Hirstoph; Schappe, Martina; Kinchel, Tom; Teller, Henryk; Shirok, Hartmut; Klar, Juergen; Jimenez, Nunez Eloisa; (352 pag.)KR2015/137095; (2015); A;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics