- Synthesis of functionalized 2H-1-benzopyrans by DBU-catalyzed reactions of salicylic aldehydes with allenic ketones and esters.
Synthesis of functionalized 2H-1-benzopyrans by DBU-catalyzed reactions of salicylic aldehydes with allenic ketones and esters.
Organic letters (2005-09-24)
Gui-Ling Zhao, Yong-Ling Shi, Min Shi
PMID16178575
ABSTRACT
[reaction: see text] DBU-catalyzed reactions of salicylic aldehydes with 3-methylpenta-3,4-dien-2-one, 3-benzylpenta-3,4-dien-2-one, or ethyl 2-methylbuta-2,3-dienoate gave the corresponding functionalized 2H-1-chromenes in good to excellent yields and good diastereoselectivities in some cases in DMSO, respectively.