Undecane → 4-(2-fluorobenzyloxy)-N-methyl-N-methoxybenzamide

Temperature

65 °C

4-(2-fluorobenzyloxy)benzoic acid (P2, 5.5 g, 22.3 mmol) was suspended in thionyl chloride (16.5 mL) and heated to 65° C. and held for 3 hours during which time the reactor was kept under a slow sweep of nitrogen. The mixture was then concentrated to a thick oil under hi vac to remove all traces of residual thionyl chloride. The residue was then diluted in CH2Cl2 (20 mL) and cooled to 0° C. In a separate flask, a solution of diaza(1,3)bicycle[5.4.0]undecane (DBU, 8.0 mL, 8.15 g, 53.52 mmol) and N-methoxy-N-methyl amine hydrochloride (2.61 g, 26.76 mmol) in CH2Cl2 (20 mL) was made and slowly added to the solution at 0° C. After warming to 20-25° C., the mixture was washed with 1 M HCl and then with a saturated NaHCO3 solution. After drying over Na2SO4, the solution was concentrated to a thick residue. The mixture was then purified by flash column chromatography eluting with 0→100% EtOAc/hexanes (gradient). Concentration of the fractions containing the title compound gave an oil that crystallized upon standing (6.0 g, 93% yield).

1. concentrationThe mixture was then concentrated to a thick oil under hi vac
2. customto remove all traces of residual thionyl chloride
3. additionThe residue was then diluted in CH2Cl2 (20 mL)
4. temperaturecooled to 0° C
5. additionslowly added to the solution at 0° C
6. temperatureAfter warming to 20-25° C.
7. washthe mixture was washed with 1 M HCl
8. dry with materialAfter drying over Na2SO4
9. concentrationthe solution was concentrated to a thick residue
10. customThe mixture was then purified by flash column chromatography
11. washeluting with 0→100% EtOAc/hexanes (gradient)
12. additionConcentration of the fractions containing the title compound
13. customgave an oil that
14. customcrystallized

ORD record

ord-29c3bad77b8746d7b506312e0a248605

Source dataset

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08759542B2