Oxidation of ylide precursors to vicinal tricarbonyls. Applications in vincamine alkaloid synthesis

Article abstract of DOI:10.1016/S0040-4020(01)88248-X

Attachment of carbethoxyalkyl residues to an α,β-diketo ester provides dielectrophilic species applicable to the synthesis of the vincamine alkaloids, eburnamonine and tacamonine. The required vicinal tricarbonyl aggregates were formed by oxidation of suitable ylide precursors with ozone or singlet oxygen.