Synthesis of 3-alkenyl-2-arylchromones and 2,3-dialkenylchromones via acid-catalysed retro-Michael ring opening of 3-acylchroman-4-ones

David S. Clarke, Christopher D. Gabbutt, John D. Hepworth, B. Mark Heron

Research output: Contribution to journalArticle

21 Citations (Scopus)


3-Acylchromones and 3-acylflavones, readily available by acylation of 2′-hydroxydibenzoylmethane with acid anhydrides in the presence of base, undergo efficient conjugate reduction with NaBH4 in pyridine to give the corresponding chroman-4-ones/flavanones in high yields. The reduction is both regio- and chemoselective. Treatment of the chroman-4-ones with MeSO 3H generates the 3-alkenyl-2-arylchromones by a dehydrative rearrangement initiated by retro-Michael cleavage of the pyranone ring. This reduction-rearrangement sequence can be extended to 2-alkyl-3-alkenoylchromones to generate 3-alkenyl-2-styrylchromones, the first examples of 2,3-dialkenylchromones.

Original languageEnglish
Pages (from-to)5515-5519
Number of pages5
JournalTetrahedron Letters
Issue number33
Early online date1 Jul 2005
Publication statusPublished - 15 Aug 2005
Externally publishedYes


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