New downstream synthetic route of 18699-87-1

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,18699-87-1, its application will become more common.

Electric Literature of 18699-87-1 ,Some common heterocyclic compound, 18699-87-1, molecular formula is C6H6N2O2, 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.

Add to a 3 neck flask containing 500 mL of absolute ethanol under N2, 2.2 g (0.0956 g-atom) of sodium. After all the sodium reacts, add diethyl oxalate (98 mL) dropwise, and then add compound 2a-1 (one equivalent). The color turns from light yellow to brown upon addition. Allow the resulting solution to stand for two days at rt. Treat the orange mixture with SN HCl (pH=1), collect the precipitate by filtration and wash the filter cake with 100 mL EtOH and 200 mL di-isopropyl ether to afford 3a-1 as 2-hydroxy-3-(3-nitro-pyridin-2-yl)-acrylic acid ethyl ester (R4H, 20 g, 86%) or its tautomeric ketoester or as a mixture of keto-enol tautomers. 1H NMR (DMSO-d6) delta 8.83 (dd, 1H, J=1.1, 5.0 Hz), 8.65 (dd, 1H, J=1.5, 8.4 Hz), 7.56 (dd, 1H, J=5.0, 8.4 Hz), 7.11 (s, 1H), 3.47 (bs, 1H), 4.28 (q, 2H, J=7.1 Hz), 1.30 (t, 3H, J=7.0 Hz).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,18699-87-1, its application will become more common.

Reference:
Patent; Aventis Pharmaceuticals Inc.; US2005/131012; (2005); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem