【摘 要】
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The efficient cleavage of carbon-oxygen (C-O) bond is highly important for the transformation of oxygen-rich biomass and industry chemicals.Herein,an efficient[3+3]annulation of β-ketoethers with cyclopropenones in the presence of catalytic base has been
【机 构】
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NMPA Key Laboratory for Research and Evaluation of Innovative Drug,Collaborative Innovation Center o
论文部分内容阅读
The efficient cleavage of carbon-oxygen (C-O) bond is highly important for the transformation of oxygen-rich biomass and industry chemicals.Herein,an efficient[3+3]annulation of β-ketoethers with cyclopropenones in the presence of catalytic base has been de-veloped,which proceeds through the C(sp3)-O bonds cleavage in β-ketoethers and C-C bond cleavage in cyclopropenones under transition-metal free conditions.The cleavage of C(sp3)-O bonds in alkyl alkyl ethers and aryl alkyl ethers was realized.The reaction featured excellent functional group compatibility and chemoselectivity,affording various 2-pyrones in good to excellent yields under mild conditions and simple operation.
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