Synthetic Route of 53636-68-3 , The common heterocyclic compound, 53636-68-3, name is 3-Amino-5-chloropicolinic acid, molecular formula is C6H5ClN2O2, 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 2;. Preparation of 3-Amino-5-chloro-pyridine-2-carboxylic acid methyl ester; Heat at 90 C a mixture of 5-chloro-3-nitro-pyridine-2-carbonitrile (1.0 g, 5.90 mmol) and tin (II) chloride (6.79 g, 29.5 mmol) in ethanol (10 mL) for 3 h. Evaporate the solvent under reduced pressure, add a solution of 35% hydrochloric acid (5 mL) and reflux the mixture for 6 h. Concentrate the reaction in vacuo to dryness and dissolve the resulting residue in methanol (20 mL). Add thionyl chloride (0.95 mL, 7.08 mmol) at room temperature and heat the mixture at 90 C for 24 h. Remove the solvent under reduced pressure, add ethyl acetate, and wash with a saturated solution of sodium bicarbonate. Separate the organic layer, dry over sodium sulfate, filter, and concentrate under reduced pressure. Purify the residue using silica gel chromatography, eluting with ethyl acetate to afford the title compound (0.77 g, 70%). H-NMR (CDCl3, 3 00 MHz): 8 3.97 (s, 3 H) ; 5.85 (bs, 2 H) ; 7.06 (d, J = 2.0 Hz, 1H), 7.97 (d, J = 2.0 Hz, 1H).
The synthetic route of 53636-68-3 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; ELI LILLY AND COMPANY; WO2005/97805; (2005); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem