摘要:
PROBLEM TO BE SOLVED: To provide a method of extracting asymmetric β-diketone compounds from β-diketone compounds.SOLUTION: A method of extracting asymmetric β-diketone compounds from β-diketone compounds comprising asymmetric β-diketone compounds and at least one symmetric β-diketone compound comprises: (A) a step of adjusting the pH of a mixed solution of β-diketone compounds and water to 11.5 or higher to dissolve β-diketone compounds in water to prepare a solution of β-diketone compounds; and (B) a step of adjusting the pH of the solution of the β-diketone compounds to 9.5 or lower and recovering asymmetric β-diketone compounds of formula (1) separated from the solution of the β-diketone compounds. The extracting method includes additionally one or both of (a) a step of setting, in the step (A) the upper limit of pH of the mixed solution as 12.5 to prepare a solution of β-diketone compounds and bringing a hydrophobic solvent into contact with the solution of β-diketone compounds and (b) a step of setting, in the step (B), the lower limit of the pH of the solution of β-diketone compounds as 8.0.