| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a specific hydroxycarboxylic acid as a crystal in a high yield and in a high purity. <P>SOLUTION: A method for crystallizing a compound (1) represented by formula (1) includes mixing a water-miscible solvent-rich solution of the compound (1) and water, wherein a necessary suspension amount of a slurry is previously prepared in order to suppress oiling and scaling of the compound (1), and thereafter, a regular crystallization is carried out in the presence of the slurry. The necessary suspension amount is preferably ≤30 wt.% with respect to the total amount of the compound (1) at the completion of the regular crystallization. In the formula, R is CH<SB POS="POST">3</SB>, CH<SB POS="POST">2</SB>OH, CH<SB POS="POST">2</SB>OCOR<SP POS="POST">1</SP>, CO<SB POS="POST">2</SB>R<SP POS="POST">2</SP>, CONR<SP POS="POST">3</SP>R<SP POS="POST">4</SP>, OH, CH<SB POS="POST">2</SB>OR<SP POS="POST">1</SP>, or CH<SB POS="POST">2</SB>NR<SP POS="POST">3</SP>R<SP POS="POST">4</SP>(wherein R<SP POS="POST">1</SP>is a 1-5C alkyl; R<SP POS="POST">2</SP>is H or a 1-5C alkyl; R<SP POS="POST">3</SP>and R<SP POS="POST">4</SP>are each independently H or a 1-5C alkyl); a and b are both double bonds, or one thereof is a single bond and the other is a double bond, or a and b are both single bonds. <P>COPYRIGHT: (C)2012,JPO&INPIT |
