Nitric Acid → 1,2-Dichloro-1,2-difluoro-1-nitroethyl trifluoroacetate

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Reaction Steps

Chlorofluoronitroacetic Acid, Oleum-Trifluoroacetic Acid Procedure. A solution of 100% nitric acid (5 mL) and trifluoroacetic acid (4.2 mL, 54 mmol) in 30% oleum (6 mL) was added over 25 min to 1,2-dichlorodifluoroethylene (7.5 g, 56 mmol) at 10°-15° C. The mixture was stirred for 60 min at 10°-14° C. The organic layer was separated, and fractionally distilled to give 2.1 g (14.5%) of 1,2-dichloro-1,2-difluoro-1-nitroethyl trifluoroacetate, as a 50:50 mixture of diasterimers, bp 48°-50° C. (0.5 mm): 19F NMR (CDCl3 ) δ -76.27 (s, 6 F), -77.50 (s,1 F), -78.49 (s, 1F), -94.37 (s, 1 F), -95.30 (s, 1 F). The second fraction contained 4.0 g of chlorofluoronitroacetic acid, bp 55°-65° C. (0.5 mm), identical to the authentic material prepared above. The oleum layer was heated to 80° C. under vacuum (0.5 mm) to give an additional 1.61 g (63% combined yield) of chlorofluoronitroacetic acid.

Provenance & Evidence