Sulfuric Acid → 3-Benzyloxy-5-hydroxypyridine

The 5-(phenylmethoxy)-3-pyridylamine (1.61 g, 8.00 mmol) was stirred into concentrated sulfuric acid (1.7 mL), water (2.5 mL) and ice (4 g). This mixture was allowed to stir for 10 min until the solution became homogeneous. To this cold, stirring solution was added a solution of sodium nitrite (552 mg, 8.00 mmol) in water (2 mL). The mixture was allowed to stir for 10 min. A boiling solution of concentrated sulfuric acid (5 mL) and water (4 mL) was added. The mixture was heated until all solids dissolved. Ice was added to cool the reaction. The pH was adjusted to 8 with 10% NaOH solution and saturated NaCl solution was added. The product was extracted with ethyl acetate (4×100 mL). The combined ethyl acetate extracts were dried (Na2SO4), filtered, concentrated by rotary evaporation and briefly vacuum to give 1.52 g (94.4%).

1. stirringTo this cold, stirring solution
2. stirringto stir for 10 min
3. temperatureThe mixture was heated until all solids
4. dissolutiondissolved
5. additionIce was added
6. temperatureto cool
7. customthe reaction
8. additionwas added
9. extractionThe product was extracted with ethyl acetate (4×100 mL)
10. dry with materialThe combined ethyl acetate extracts were dried (Na2SO4)
11. filtrationfiltered
12. concentrationconcentrated by rotary evaporation and briefly vacuum
13. customto give 1.52 g (94.4%)

ORDレコード

ord-0cc9d436252e46e9ae914c901114466e

出典データセット

uspto-grants-2003_09

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06627648B1