In 1954,Chemische Berichte included an article by Heyns, Kurt; Vogelsang, Gerhard. Application of 857433-67-1. The article was titled 《γ-Pyrones and γ-pyridones. I. The constitution of the hydroxy-γ-pyrones and hydroxy-γ-pyridones》. The information in the text is summarized as follows:
Methylation of kojic acid (I) according to Campbell, et al. (C.A. 44, 4468h), gives 54-65% 5-methoxy-2-hydroxymethyl-4-pyrone (II), m. 165°. Treating 25 g. II in 125 cc. concentrated HNO3 (d. 1.41) 70-80 hrs. at 20° with 25 cc. HNO3 (d. 1.52) and pouring the mixture onto 150 g. ice and 750 cc. H2O give 5-methoxy-4-pyrone-2-carboxylic acid (III), m. 282°, also obtained in 2-g. yield when a strong current of air is passed through 8 g. II in 500 cc. H2O containing 10 g. 10% Pd-C catalyst 30 hrs. at 65° and the pH is adjusted from time to time to 5-6. Heating II with concentrated NH4OH in a pressure bottle gives 75-87% 5-methoxy-2-hydroxymethyl-4-pyridone, m. 173-4°, oxidized with concentrated and fuming HNO3 (5:1) to 70-85% 5-methoxy-4-pyridone-2-carboxylic acid, m. 265°, which, heated with SOCl2, gives 94.5% 4-chloro-5-methoxy-2-pyridine-carbonyl chloride (IV), purified by sublimation in vacuo. Saponification of 39 g. IV in H2O in the presence of a little NaOH gives the free acid (V), m. 209° (Me ester, m. 166-7°). Reduction of 10 g. V in 150 cc. 10% HCl with 10 g. Sn and a small amount of HgCl2 several days at 20°, evaporation of the filtered solution, and precipitation of the Sn with H2S give 81.2% 5-methoxy-2-pyridinecarboxylic acid-HCl (VI), m. 202-3°. Refluxing 4 g. VI with 20 cc. 70% HI 3 hrs., diluting the mixture with 20 cc. H2O, decolorizing it with Na2SO3, and adjusting the pH to 3-4 give 51.2% 5-hydroxy-2-pyridinecarboxylic acid, also obtained in 92-5% yield when 7.5 g. 2-carboxy-5-pyridinesulfonic acid (VII) is heated 1 hr. at 220° with 30 g. NaOH and 6 cc. H2O in a Ni crucible and the solution of the melt in 300 cc. H2O is adjusted to pH 4-5 (Me ester, prepared with MeOH and HCl, m. 191-2°). Heating 80 g. 2-picoline in 400 g. 27% oleum in the presence of 2.5 g. HgCl2 at 220-30° gives 40% 2-methyl-5-pyridinesulfonic acid (VIII), m. above 280°. Adding (1 hr.) 126 g. KMnO4 to 63 g. Na salt of VIII in 1 l. gently boiling H2O gives 46.1% VII, m. 287° (decomposition). The compounds are identified by paper chromatography with BuOH-AcOH-H2O (180:20:50), which gives the following Rf values: III 0.26, I 0.80, 5-hydroxy-4-pyrone-2-carboxylic acid 0.27, 5-hydroxy-2-hydroxymethyl-4-pyridone 0.71, and 5-hydroxy-4-pyridone-2-carboxylic acid 0.30 (0.04% bromocresol green in 50% EtOH and 0.1% FeCl3 solution as developers). The position of the 5-OH group in the pyrone and pyridone derivatives obtained from meconic acid and from I is confirmed (cf. Belonossov, C.A. 45, 5650g). In the experiment, the researchers used Methyl 4-chloro-5-methoxypicolinate(cas: 857433-67-1Application of 857433-67-1)
Methyl 4-chloro-5-methoxypicolinate(cas: 857433-67-1) belongs to pyridine. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. As ligands, solvents, and catalysts they facilitate reactions; thus descriptions of these new ligands and their applications abound each year.Application of 857433-67-1