[OH-].[K+].[Br:3][C:4]1[C:9]([OH:10])=[CH:8][CH:7]=[CH:6][N:5]=1.[Na+].C(N(CC([O-])=O)CC([O-])=O)CN(CC([O-])=O)C[C:16]([O-])=[O:17].[Na+].[Na+].[Na+].C=O>O.C(O)(=O)C>[Br:3][C:4]1[C:9]([OH:10])=[CH:8][CH:7]=[C:6]([CH2:16][OH:17])[N:5]=1Potassium hydroxide (85% assay, 113.8 g, 1.73 mol) was dissolved in distilled water (750 ml) and to the solution was added 2-bromo-3-hydroxypyridine (300 g, 1.72 mol), ethylenediaminetetraacetic acid sodium salt (2 mmol %, 13.1 g, 0.034 mmol) and formalin (3741% w/v 470 ml, 5.95 mmol). The stirred mixture was heated at 90°-95° C. until the assay (HPLC) of remaining starting material fell below 3% (approx 5 h) . The reaction mixture was then cooled to room temperature and glacial acetic acid (103 ml) added and stirred for a further 2h. The precipitated solid was filtered from the mixture and the filtrate saturated with sodium chloride (310 g). The resulting solution was extracted with ethyl acetate (4×280ml). The combined organic extracts were dried and evaporated to dryness keeping the temperature below 85° C. The residue was assayed by HPLC to determine the quantity of contained 2-bromo-3-hydroxy-6-hydroxymethylpyridine. The yield was typically 65%.
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