Reaction of mono-epoxidized conjugated linoleic acid ester with boron trifluoride etherate complex

• Published in: Lipids Vol. 39; no. 6; pp. 583 - 587
• Main Authors: Jie, M.S.F.L.K, Lam, C.N.W
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer‐Verlag 01.06.2004; Springer Nature B.V
• Subjects: Boranes - chemistry; Boron; chemical reactions; epoxidation; Epoxy Compounds - chemistry; Esters - chemistry; Linoleic Acids, Conjugated - chemistry; Molecular Structure
• ISSN: 0024-4201; 1558-9307
• DOI: 10.1007/s11745-004-1267-6

The reaction of methyl 11, 12‐E‐epoxy‐9Z‐octadecenoate (1) with boron trifluoride etherate furnished a mixture of methyl 12‐oxo‐10E‐octadecenoate (3a) and methyl 11‐oxo‐9E‐octadecenoate (3b) in 66% yield. Methyl 9, 10‐Z‐epoxy‐11 E‐octadecenoate (2) with boron trifluoride etherate furnished a mixture of methyl 9‐oxo‐10 E‐octadecenoate (4a, 45%) and methyl 10‐oxo‐11 E‐octadecenoate (4b, 19%). A plausible mechanism is proposed for these reactions, which involves the attack on the epoxy ring system by BF3, followed by deprotonation, oxo formation, and double bond migration to give a mixture of two positional α,β‐unsaturated C18 enone ester derivatives (3a/3b, 4a/4b). The structures of these C18 enone ester derivatives (3a/3b, 4a/4b) were identified by a combination of NMR spectroscopic and mass spectrometric analyses.