Preparation of conjugated dienoates with Bestmann ylide: Towards the synthesis of zampanolide and dactylolide using a facile linchpin approach

• Main Authors: Jingjing Wang, Samuel Z. Y. Ting, Joanne E. Harvey
• Format: Article
• Language: English
• Published: Beilstein-Institut 2015-10-01
• Series: Beilstein Journal of Organic Chemistry
• Subjects: Bestmann ylide; dactylolide; dienoate; (triphenylphosphoranylidene)ketene; zampanolide
• Online Access: https://doi.org/10.3762/bjoc.11.197

Bestmann ylide [(triphenylphosphoranylidene)ketene] acts as a chemical linchpin that links nucleophilic entities, such as alcohols or amines, with carbonyl moieties to produce unsaturated esters and amides, respectively. In this work, the formation of α,β,γ,δ-unsaturated esters (dienoates) is achieved through the coupling of Bestmann ylide, an alcohol and an α,β-unsaturated aldehyde. Primary and secondary alcohols, including allylic alcohols, are suitable substrates; the newly formed alkene has an E-geometry. Strategically, this represents a highly efficient route to unsaturated polyketide derivatives. A linchpin approach to the synthesis of a major fragment of the natural products zampanolide and dactylolide is investigated using Bestmann ylide to link the C16–C20 alcohol with the C3–C8 aldehyde fragment.