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

Participants

Reaction Conditions

Reaction Steps

Methyl 3-morpholin-4-ylacrylate (96.3%, 8.5 g, 50 mmol) and triethylamine (5.2 g, 50 mmol) were initially charged in toluene (250 ml) and cooled to −30° C. At this temperature, difluoroacetyl fluoride (5.0 g, 50 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. Under reduced pressure, the reaction mixture was freed from the solvent. The residue obtained was 15.5 g of an orange solid which, according to quant. 1H-NMR, consisted to 66.4% of methyl 4,4-difluoro-3-oxo-2-(morpholin-4-ylmethylidene)butyrate (yield: 82%). 1H-NMR (CDCl3): δ=3.4 (m, 2H), 3.7 (m, 2H), 3.75 (s, 3H), 3.85 (m, 2H), 6.6 (t, 1H), 7.85 ppm (s, 1H).

Provenance & Evidence