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Synthesis of Heterobiaryl 4-Aryl Furans through a Base-Promoted Decarboxylative Propargylation/Cycloisomerization
Sasa Wang1,2, Meimei Song1, Xiuguang Li1
1Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Guangxi Collaborative Innovation Center for Chemistry and Engineering of Forest Products, Guangxi University for Nationalities, Nanning 530006, China.
Abstract:
A transition-metal-free synthesis of heterobiaryl 4-aryl furans through a base-promoted decarboxylative propargylation/cycloisomerization annulation of ethynyl benzoxazinanones and readily accessible β-keto esters or 1,3-diketones has been developed. A series of novel heterobiaryl 4-aryl furans were accessed efficiently in the presence of base under mild reaction conditions. This protocol is significant for probing the reaction mechanism of ethynyl benzoxazinanones and even other propargylic compounds.
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