Water → 4-azepan-1-yl-3-nitrobenzoic acid

Temperature

60 °C

A mixture of ethyl 4-fluoro-3-nitrobenzoate (Chontech 01072; 500 mg; 2.35 mmol; 1 eq.) and hexamethyleneimine (Fluka 52660; 697.89 mg; 7.04 mmol; 3 eq.) in DMF (2 mL) was stirred at 60° C. for 4 hours. The reaction mixture was then partitioned between ethyl acetate and aq. NH4Cl. The organic layer was washed with brine, dried over magnesium sulfate and concentrated in vacuo to give a yellow solid. The latter was taken up in THF (5 mL) and lithium hydroxide (280.86 mg; 11.73 mmol; 5 eq.) then water (5 mL) were added. The reaction mixture was stirred at room temperature for 16 hours then the solvent was evaporated and the residue was diluted with water. After acidification to pH 5 with AcOH, the resulting precipitate was filtered and dried under high vacuum to afford the title compound (534 mg, 86%) as a yellow solid.

1. customThe reaction mixture was then partitioned between ethyl acetate and aq. NH4Cl
2. washThe organic layer was washed with brine
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated in vacuo
5. customto give a yellow solid
6. stirringThe reaction mixture was stirred at room temperature for 16 hours
7. customthe solvent was evaporated
8. additionthe residue was diluted with water
9. filtrationAfter acidification to pH 5 with AcOH, the resulting precipitate was filtered
10. customdried under high vacuum

ORD record

ord-d1349e267af64a3b972e6cb79193dd7a

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08889668B2