Synthetic Route of 2739-98-2 ,Some common heterocyclic compound, 2739-98-2, molecular formula is C9H11NO2, 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.
2-Hydroxypyrazolo[1,5-a]pyridine (I). After a mixture of ethyl 2-pyridylacetate (3.00 g), HAS (0.60 g) and water (3 ml) was stirred at room temperature for 30 h, it was extracted with CH2 CL2. The aqueous layer was made alkaline with 10% Na2 CO3 to pH 9 and was extracted with CH2 CL2. The organic extracts were combined, and after drying over MgSO4 the solvent was evaporated. The residual oil was shaken with Et2 O-10% Na2 CO3. After the ether-layer was dried over MgSO4, the solvent was evaporated to give the starting ethyl 2-pyridylacetate (2.11 g, 70.5% yield). The pH of the basic aqueous layer was adjusted to 5 by adding AcOH to precipitate brown powder (0.36 g, 45.9% yield, based upon the consumed starting material). Recrystallization from benzene-hexane gave 2-hydroxypyrazolo[1,5-a]pyridine (0.32 g, 40.7%) mp 127-128 C., as colorless leaflets. UV lambdamaxmeOH (log epsilon): 232 (4.59), 280.5 (3.09), 310 (3.10). STR85 3000, 1635, 1535, 1258. Found: C, 62.53; H, 4.48; N, 20.98%. Calcd for C7 H6 ON2: C,62.68; H, 4.51; N, 20.98%.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,2739-98-2, its application will become more common.
Reference:
Patent; Boehringer Mannheim GmbH; US5334505; (1994); A;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem