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A copper(II) perchlorate-promoted tandem reaction of internal alkynol and salicyl N-tosylhydrazone: direct access to isochromeno[3,4-b]chromene. | LitMetric
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A copper(II) perchlorate-promoted tandem reaction of internal alkynol and salicyl N-tosylhydrazone: direct access to isochromeno[3,4-b]chromene.

Hai Xiao Siyang Xu Rui Wu Xiao Yue Ji Xin Yan Wu Pei Nian Liu

Chem Commun (Camb)

Shanghai Key Laboratory of Functional Materials Chemistry, Key Lab for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Meilong Road 130, Shanghai 200237, China.

Published: August 2014

A copper(ii) perchlorate-promoted tandem reaction of internal alkynol and salicyl N-tosylhydrazone provides a novel, concise method for constructing isochromeno[3,4-b]chromene in 35-94% yields. The tandem reaction involves cycloisomerization, formal [4+2] cycloaddition and an elimination process.

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 Source
http://dx.doi.org/10.1039/c4cc02862gDOI Listing

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