Methanol → 2H-Hexafluoro(2-methylpropanoic acid)

Participants

Reaction Steps

A mixture of ethyl 2-(4-chlorophenoxy)-3,3,3-trifluoro2-trifluoromethylpropionate (14.6 g.), 4.5 N-aqueous potassium hydroxide (19.2 ml.) and methanol (35 ml.) is stirred at ambient temperature for 21/4 hours. The resulting solution is diluted with water and washed with ether. The aqueous phase is acidified with concentrated hydrochloric acid, and extracted with ether. The extract is washed with water, dried with sodium sulphate and evaporated. The residue is sublimed twice at 100° C. and 0.3 mm. pressure, and the sublimate is washed with light petroleum (b.p. 30°-40° C.) to give 2-(4-chloropheonxy)- 3,3,3-trifluoro-2-trifluoromethylpropionic acid, m.p. 81°-83° C. (5.1 g.). The acid may be further purified by crystallisation (prisms) from light petroleum (b.p. 60°-80° C.) followed by sublimation, which yields material of m.p. 82°-83° C.

Provenance & Evidence