Related Products of 1207557-35-4 ,Some common heterocyclic compound, 1207557-35-4, molecular formula is C11H11BrN2O3, 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.
Step B: DecarboxylationA solution of ethyl 6-bromo-4-methoxylpyrazolo[l,5-a]pyridine-3-carboxylate (15, 5.2 g, 18.24 mmol) in HBr (100 ml, 884 mmol) was heated to 100 0C for 1 hour. After cooling to 0 0C, IM NaOH (182 ml, 912 mmol) was used to neutralize the solution. The reaction mixture was diluted in ethyl acetate, washed with saturated aqueous sodium hydroxide (IN) and brine then dried over Na2SO4. After filtration and concentration, the residue was purified by column chromatography (0-35% EtOAc in hexanes, linear gradient) to give 6-bromo-4- methoxypyrazolo[l,5-alpha]rhoyridine (16, 2.475 g, 10.90 mmol, 60 % yield). MS APCI: (M + H]+ m/z 228.1.; Scheme 2.Molecules of type 21 were prepared according to scheme 2. O- Mesitylenesulfonylhydroxylamine (1) was used to access W-imino-pyridinium mesitylenesulphonate 14. [3+2] Cyclization of 2 with ethyl propiolate yields pyrazolopyridine 15. Decarboxylation in neat hydrobromic acid afforded 16. Functional ization of the 6-position of the pyrazolopyridine core is accomplished via a Suzuki coupling reaction to install aryl or heteToaromatic functionality (17) using known or commercially available boronic acids or esters. For specific boronic ester examples, see WO 2004052286 A2 and WO 2007085873 Al . Halogenation via reaction with //-iodosuccinimide enables a second Suzuki coupling of iodide 18 with thiophcnc boronic ester to yield coupling product 19. Hydrolysis of the ester yielded acid 20 and subsequent coupling with an amine yielded target 21.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,1207557-35-4, its application will become more common.
Reference:
Patent; MERCK & CO., INC.; KATZ, Jason; KNOWLES, Sandra, L.; JEWELL, James, P.; SLOMAN, David, L.; STANTON, Matthew, G.; NOUCTI, Njamkou; WO2010/17046; (2010); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem