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Synthesis of dihydrobenzofurans with quaternary carbon center under mild and neutral conditions. | LitMetric

A new method has been developed for the construction of dihydrobenzofurans from O-aryloxime ethers bearing an α-cyano group using a sequential regioselective isomerization/[3,3]-sigmatropic rearrangement/cyclization reaction in MeOH without any catalysts under neutral conditions at ambient temperature. The current transformation provides environmentally benign and atom-economical access to a variety of dihydrobenzofurans containing a quaternary carbon from readily available cyclic and acyclic oxime ethers.

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http://dx.doi.org/10.1021/ol401897uDOI Listing

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