Lie Ken Jie, M. S. F. et.al.: Novel halo-oxo-allenic fatty ester derivatives
from epoxidized methyl santalbate (methyl
trans-11-octadecen-9-ynoate)
- Author(s): Lie
Ken Jie, M. S. F.; Lau, M. M. L.; Lam, C. N. W.; Alam, M. S.;Metzger,
J. O.; Biermann, U.
- Title: Novel halo-oxo-allenic fatty ester derivatives from epoxidized
methyl santalbate (methyl trans-11-octadecen-9-ynoate)
- Date of Upload: 2003
- Article: Chemistry and physics of lipids (CHEM. PHYS. LIPIDS) (2003 Oct),
125(2), 93-101; , Department of Chemistry, The University of Hong Kong,
Pokfulam Road, Hong Kong, China; University of Oldenburg, Department of
Chemistry
- Keywords: sustainable development, renewable feedstock, vegetable
oil, plant oil, Halo-oxo-allenic fatty ester, epoxidation, C18 enynoic,
santalbic acid
- Abstract:
- Methyl santalbate (methyl trans-11-octadecen-9-ynoate) from Sandal wood
seed oil, Santalbum alum) was epoxidized to methyl
trans-11,12-epoxy-octadec-9-ynoate (1). Treatment of compound 1 with
tetrabutylammonium dihydrogentrifluoride, and boron trifluoride etherate gave
the corresponding anti- (2a) (57%) and syn- (2b) (35%) fluorohydrin
derivatives, respectively. These reactions were regio- and stereoselective in
nature. The structures of the anti- and syn- isomers were confirmed by NMR
spectroscopy. Ring opening of the epoxy system of compound 1 with lithium
chloride gave the anti-chlorohydrin derivative (3) (89%). Oxidation of either
compound 2a or 2b gave the same fluoro-keto acetylenic fatty ester (4) (75%),
and compound 3 on chromic acid oxidation yielded the corresponding chloro-keto
acetylene (5) (73%). Isomerization of compounds 4 and 5 with potassium
carbonate in dichloromethane furnished the requisite fluoro-allenic (6) (63%,
methyl 11-fluoro-12-oxo-9,10-octadecadienoate) and chloro-allenic (7) (80%,
methyl 11-chloro-12-oxo-9,10-octadecadienoate) C(18) fatty esters. All
products were confirmed by a combination of spectrometric and spectroscopic
techniques.
- URL: http://www.chemie.uni-oldenburg.de/oc/metzger/publikationen/pdf/100.pdf
(application/pdf)
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