Triethylamine → Methyl 4,4-difluoro-3-oxo-2-(2,6-dimethylmorpholin-4-ylmethylidene)butyrate

Temperature

-30 °C

Methyl 3-(2,6-dimethylmorpholin-4-yl)acrylate (93.5%, 17.5 g, 82 mmol) and triethylamine (8.8 g, 87 mmol) were initially charged in toluene (150 ml) and cooled to −30° C. At this temperature, difluoroacetyl fluoride (10.0 g, 100 mmol) was introduced. The reaction mixture was stirred at −30° C. for 3 h and then, over a period of 1 hour, warmed to room temperature. The reaction mixture was washed with deionized water (100 ml). After separation of the phases, the aqueous phase was extracted once with toluene (100 ml). The toluene phases were combined and washed with an aqueous saturated NaCl solution (100 ml), and the solvent was then removed under reduced pressure. The residue obtained was 21.4 g of an orange solid which, according to GC analysis, consisted to 90.8% of methyl 4,4-difluoro-3-oxo-2-(2,6-dimethylmorpholin-4-ylmethylidene)butyrate (yield: 85.3%). 1H-NMR (CDCl3): δ=1.2 (s, 3H), 1.25 (s, 3H), 2.95 (m, 1H), 3.25 (m, 1H), 3.5 (m, 1H), 3.75 (m, 2H), 3.8 (s, 3H), 6.6 (t, 1H), 7.85 ppm (s, 1H).

1. waitover a period of 1 hour
2. temperaturewarmed to room temperature
3. washThe reaction mixture was washed with deionized water (100 ml)
4. customAfter separation of the phases
5. extractionthe aqueous phase was extracted once with toluene (100 ml)
6. washwashed with an aqueous saturated NaCl solution (100 ml)
7. customthe solvent was then removed under reduced pressure
8. customThe residue obtained

ORD record

ord-a5342a53ac4647eca6e3cba3b5ae3249

Source dataset

uspto-grants-2012_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08314233B2