An efficient countercurrent distribution method for the large-scale isolation of dimorphecolic acid methyl ester

• Published in: Chemistry and physics of lipids Vol. 71; no. 2; pp. 187 - 196
• Main Authors: Tassignon, P., de Waard, P., de Rijk, T., Tournois, H., de Wit, D., de Buyck, L.
• Format: Journal Article
• Language: English
• Published: Elsevier Ireland Ltd 23.05.1994
• Subjects: 1H and 13C-NMR spectroscopy; Countercurrent distribution; Crystallization; Dimorphecolic acid methyl ester; Methyl 9-oxo-10,12-E,E-octadecadienoate; Countercurrent distribution; Dimorphecolic acid methyl ester; 1H and 13C-NMR spectroscopy; Methyl 9-oxo-10,12-E,E-octadecadienoate; Crystallization
• ISSN: 0009-3084; 1873-2941
• DOI: 10.1016/0009-3084(94)90070-1

Effective procedures are reported for isolating and producing dimorphecolic acid (1) and its methyl ester (2) from Dimorphotheca pluvialis seed oil. The methods are suitable even for kilogram-scale production. The acid 1 was prepared by enzymatic hydrolysis of the oil and isolated by crystallization at low temperature. The ester (2) was obtained by methoxide-catalyzed transesterification of the glycerides followed by a countercurrent separation using four vessels and fourteen transfers with the two-phase system 90% aq. methanol-hexane. Methyl 9-oxo-10,12-E,E-octadecadienoate (3) (0.5 to 4%) was observed by GC and GC-MS and characterized by its reduction with sodium borohydride to racemic 2 and by its formation from 2 by Oppenauer oxidation. The complete assignment of the 1H and 13C-NMR signals of 1 and 3 has been carried out using 2D homonuclear and heteronuclear NMR experiments.