PURPOSE: To obtain the titled compound in high selectivity useful as an intermediate raw material for a fluorine-containing organic compound, by introducing hexafluoropropylene oxide successively into a reaction medium wherein a polor nonproton solvent, a source for a fluorine anion, and the desired substance coexist.
CONSTITUTION: Hexafluoropropylene oxide is introduced at a temperature of 0W 5°C, under pressure of 2kg/cm2 by intermittent or continuous addition successively into a reaction medium(preferably, in substantially anhydrous state) wherein a polar nonproton solvent, a catalyst of source for a fluorine anion e.g., KF, etc., and perfuloro(2-methyl-3-oxa-hexanoyl fluoride) shown by the formula, the desired substance coexist previously, so that it is selectively dimerized to give the desired compound shown by the fromula. The amount of the compound shown by the formula which is previously present in the reaction medium is 0.5W2 mole based on 1 mole hexafluoropropylene oxide.
MUNAKATA SEIJI
KANEKO ISAMU
Next Patent: PREPARATION OF PERFLUORO-3-OXA-4-PENTENOYL FLUORIDE