methyl 2,2,3-trifluoro-3-oxopropanoate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 624 g (4.0 mol) of methyl difluorofluoroformylacetate, 348 g (3.5 mol) of fluorosulfonic acid and 25 ml of HSbF6 (0.3 mol) was charged to a 1 liter Teflon® pot fitted with a Teflon® condenser connected to a trap cooled to -80°. The mixture was stirred and heated at 80° to 110° for about 24 h. Then, 187 g (65% yield) of crude difluoromalonyl fluoride was collected which, after trap-to-trap distillation, was analyzed by NMR at -30°. NMR (CCl4): 19F 21.0 (t, JFF 10.9 Hz, 2F, COF) and -112.4 ppm (t, JFF 10.9 Hz, 2F, CF2) with a very small amount of impurity showing at -162.1 ppm. Distillation of a 140 g sample gave 118 g of pure FCOCF2COF, b.p. -4° to -5°. Dimethyl difluoromalonate was also formed. connected to a trap cooled to -80° heated at 80° to 110° for about 24 h

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 84 g (0.54 mol) of methyl difluorofluoroformylacetate, 104 g (1.0 mol) of fluorosulfonic acid and 9 g (0.038 mol) of HSbF6 was heated at 100° to 115° for 20 h. Then, 25.6 g of volatile product, collected through a condenser in a -80° trap, and boiling in the range of -25° to +10°, was identified by IR as difluoromalonyl fluoride (66% yield) based on the stoichiometry 2 FOCCF2CO2CH3 :CF2 (COF)2. Dimethyl difluoromalonate was also formed. was heated at 100° to 115° for 20 h Then, 25.6 g of volatile product, collected through a condenser in a -80° trap boiling in the range of -25° to +10°