Synthetic Route of 372198-69-1 , The common heterocyclic compound, 372198-69-1, name is Ethyl 6-bromoimidazo[1,2-a]pyridine-3-carboxylate, molecular formula is C10H9BrN2O2, 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.
[002981 Example 4[00299] Preparation of compound 8:[00300] 1. Anethanol solution of compound 5 (12400 g in 51 L of ethanol) was added to an appropriately sized stainless steel reactor at room temperature under nitrogen atmosphere.[00301] 2. Compound 6 (9500 g) was added as a solid in one portion at room temperature.[00302] 3. The reaction mixture was heated to reflux (~78C) and stirred for 1-2 days.[00303] 4. The reaction was monitored by HPLC.[00304] 5. Upon completion, the reaction mixture was allowed to cool to room temperature.[00305] 6. NaOH solution (9884 g solid pellets dissolved in 38 L of water) was added as a stream over a30 min period at an internal temperature below 35 C.[00306] 7. The reaction mixture was heated to reflux (~78C) for 3 to 4 hours.[00307] 8. The reaction was monitored by HPLC.[00308] 9. Upon completion, the reaction mixture was cooled to an appropriate temperature to start solvent removal.[00309] 10. All ethanol (approximately 5 volumes of ethanol) was removed under vacuum at 40 to 45 C.[00310] 11. The reaction mixture was cooled to room temperature.[00311] 12. Water (57 L; 6 vol) was added at room temperature.[00312] 13. The aqueous solution was washed with ethyl acetate (2 x 38 L) to remove all organic impurities.[00313] 14. The lower aqueous layer was cooled to 0-5 C and acidified with cone. HCl (~15 L) until reaching pH 1-2.[00314] 15. The reaction mixture was stirred for 1 to 2 hours at 0 to 5 C.[00315] 16. The mixturewas filtered and the cake was washed with water (2 x 38 L) and acetone (2 x 19L) followed by drying for 1-2 hours.[00316] 17. The solid collectedwas transferred back into an appropriately sized reactor.[00317] 18. Heptane (95 L; 10 vol) was addedto the reactor; the suspension was stirred for 4 to 5 hours at roomtemperature.[00318] 19. The solidwas collected by filtration and washed with heptane (2 x 19 L).[00319] 20. The solid (15 kg) was suspended in methanol (75 L; 5 vol) at room temperature for 2 hours.[00320] 21. The suspension was filtered and the solid collected was washed with methanol (2x 5L).22. The solid was dried under vacuum at 50C to constant weight to give compound 8 as an off-white to white solid (10169 g, 83.3 % yield; HPLC purity 99.2%;1HNMR (DMSO-d6, 300 MHz) ? 9.4 (s, 1H), 8.3(s, 1H), 7.85-7.67 (m, 2H)).
The synthetic route of 372198-69-1 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; INTELLIKINE, LLC; MARTIN, Michael; WORRALL, Christopher, Peter; GANCEDO, Susanna, Del Rio; REN, Pingda; WO2013/71272; (2013); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem