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ChemicalBook CAS DataBase List 2,4-DIHYDROXY-6-METHYLPYRIDINE
3749-51-7

2,4-DIHYDROXY-6-METHYLPYRIDINE synthesis

6synthesis methods
-

Yield:-

Reaction Conditions:

Stage #1: Dehydracetic acidwith sulfuric acid at 130; for 2 h;
Stage #2: with ammonia in water at 100; for 7 h;

Steps:

28.A

A suspension of 3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione (500 g) in concentrated Η2SO4 (800 mL) was stirred at 130 0C for 2 h. The mixture was poured into ice-water. The precipitate was collected by filtration, washed with hexane, and dried at 80 0C. A suspension of the above solid in25 28% aqueous NH3 was stirred at 1000C for 7 h. To the mixture was added water (1 L) and the mixture was neutralizing with concentrated HCl. The precipitate was collected by filtration, washed with water and acetone, and dried at 80 0C to give 6-methylpyridine-2,4-diol (135 g) as a pale brown solid. 1HNMR (300 MHz, DMSO-J6, δ): 2.08 (s, 3H), 5.34-5.37 (m, IH), 5.60-5.63 (m, IH), 10.30-10.61 (m, IH), 10.92-11.15 (m, IH); ESI MS m/z 126 (M++., 100%).

References:

WO2006/35967,2006,A1 Location in patent:Page/Page column 71

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