Asymmetric Synthesis of Iridoid Derivatives Using Resolved 2-Phenylindoline as a Chiral Auxiliary
2008 (English)In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 35, 5915-5921 p.Article in journal (Refereed) Published
An asymmetric synthetic route to cis,cis-nepetalactol (component of the sex pheromone for the hop aphid, Phorodon humuli) is presented. 2-Phenylindoline was resolved to provide a chiral auxiliary for the cycloaddition of oxocitral. The resolution was made by chromatographic separation of the diastereomers of the urea derivative made from 2-phenylindoline and with (R)-(+)-alpha-methylbenzyl isocyanate, followed by reductive cleavage of the isolated diasteromers using diborane. The cycloaddition of oxocitral using (S)-2-phenylindoline yielded an enantiopure product after chromatography. Hydrolysis of the cycloaddition adduct yielded gastrolactol (3). As gastrolactol is a versatile synthon for the synthesis of iridoids, the overall procedure provides a general asymmetric route to elaborated iridoids.
Place, publisher, year, edition, pages
2008. no 35, 5915-5921 p.
Iridoid, Cycloaddition reaction, Nepetalactol, Chromatographic resolution, 2-Phenylindoline
IdentifiersURN: urn:nbn:se:kth:diva-34128DOI: 10.1002/ejoc.200800440ISI: 000261941500006ScopusID: 2-s2.0-56749088092OAI: oai:DiVA.org:kth-34128DiVA: diva2:419569
QC 201105272011-05-272011-05-262011-05-27Bibliographically approved