Catalytic Synthesis of 1H-Benzoxazolo[3,2-a]pyridin-1-ones via Formal [3 + 3] Annulations of NHC-Generated Alkynyl Acylazoliums with Benzoxazolyl Acetates and Their Photophysical Studies
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引用次数: 0
Abstract
We disclose the synthesis of a tricyclic fused N-heterocycle via the NHC-catalyzed annulation of either a ynal or an alkynyl ester with readily accessible benzoxazolyl acetate. While the annulation with ynals requires an oxidant, the reaction with alkynyl esters proceeds via the direct generation of alkynyl acylazolium intermediates with an NHC. With the dearth of catalytic processes to access these 1H-benzoxazolo[3,2-a]pyridin-1-ones from simple starting materials, this method is especially important. The photophysical properties of the products have also been evaluated.
期刊介绍:
The Journal of Organic Chemistry welcomes original contributions of fundamental research in all branches of the theory and practice of organic chemistry. In selecting manuscripts for publication, the editors place emphasis on the quality and novelty of the work, as well as the breadth of interest to the organic chemistry community.