Elsevier

Tetrahedron

Volume 23, Issue 3, 1967, Pages 1057-1064
Tetrahedron

Anthocyanidins and related compounds—XI: Catechin-flavylium salt condensation reactions

https://doi.org/10.1016/0040-4020(67)85056-7Get rights and content

Abstract

Flavylium salts and d-catechin condense oxidatively to yield crystalline 4-flavanylflavylium salts. Aerial oxidation is not involved in these condensation reactions. A 4-flavanylflavene is first formed and then oxidized by a second molecule of the flavylium salt, which is reduced to a monomeric flav-2-ene. This conclusion is supported by studies on the oxidation of model phenolic flav-2-enes. Disproportionation of a flavene, viz. VIII, to a flavylium salt and the corresponding flavan has been demonstrated unequivocally for the first time.

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  • Cited by (0)

    1

    A laboratory of the Western Utilization Research and Development Division, Agricultural Research Service, U.S. Department of Agriculture.

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