Aryllead triacetates as synthons for the synthesis of biflavonoids. Part 1. Synthesis and reactivity of a flavanonyllead triacetate
摘要:
The 8-triacetoxyplumbylflavane derivative 11 was prepared in 4 steps in 28% overall yield from 4',5,7-flavanone. It reacted with the benzofuranone allyl beta-keto ester 12 to yield a 8-(benzofuran-2-yl)flavanone 13 in 66%. Removal of the allyl ester group and cleavage of the dioxolane ring afforded the 8-(3-oxobenzofuran-2-yl)flavanone. This reaction shows that complex polyfunctional aryllead triacetates can be made and selectively coupled with activated ketones.
Aryllead triacetates as synthons for the synthesis of biflavonoids. Part 1. Synthesis and reactivity of a flavanonyllead triacetate
摘要:
The 8-triacetoxyplumbylflavane derivative 11 was prepared in 4 steps in 28% overall yield from 4',5,7-flavanone. It reacted with the benzofuranone allyl beta-keto ester 12 to yield a 8-(benzofuran-2-yl)flavanone 13 in 66%. Removal of the allyl ester group and cleavage of the dioxolane ring afforded the 8-(3-oxobenzofuran-2-yl)flavanone. This reaction shows that complex polyfunctional aryllead triacetates can be made and selectively coupled with activated ketones.