tert-Butanol → Tert-butyl 6-aminopyridine-3-carboxylate

Temperature

80 °C

A mixture of 6-amino pyridine 3-carboxylic acid (2.0 g, 14.48 mmol) and thionyl chloride (10 mL) was reflux for 3.5 h under anhydrous atmosphere. Acid chloride formation was confirmed by TLC. Excess of thionyl chloride was removed under reduced pressure on rotavapour. Triethyl amine (5 mL, 36.2 mmol) and tert-butanol (5 mL) was added to acid chloride at 0° C. under inner atmosphere and reaction mixture was heated at 80° C. for 2 h. completion of reaction was confirmed by TLC. The reaction mixture was diluted with dichloromethane (50 mL) and water (50 mL), layers were separated and aqueous layer was extracted with DCM (2×30 mL) combined organic layers were washed with water (50 mL), brine (50 mL) and dried over anhydrous sodium sulphate (50 g). The solvent was removed under reduced pressure and the residue was purified by column chromatography using 20-30% ethyl acetate in hexane. Removal of solvent from appropriate fractions under reduced pressure using rotavapour gave pure product (0.7 g).

1. temperaturewas reflux for 3.5 h under anhydrous atmosphere
2. customExcess of thionyl chloride was removed under reduced pressure on rotavapour
3. customcompletion of reaction
4. customwere separated
5. extractionaqueous layer was extracted with DCM (2×30 mL)
6. washwere washed with water (50 mL), brine (50 mL)
7. dry with materialdried over anhydrous sodium sulphate (50 g)
8. customThe solvent was removed under reduced pressure
9. customthe residue was purified by column chromatography
10. customRemoval of solvent from appropriate fractions under reduced pressure

ORD record

ord-8d9df7bcc1fe4a3f8a915bfe5769f5d4

Source dataset

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09340506B2