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The alkynyl moiety as a donor for donor-acceptor cyclopropanes. | LitMetric

The first trans-selective [3 + 2]-cycloaddition of a new type of donor-acceptor cyclopropane with aldehydes is presented. 2,2-Disubstituted cyclopropanes, bearing an alkyne moiety as the sole donor entity, were transformed to highly substituted tetrahydrofurans in the presence of a catalytic amount of Ca(NTf2)2/Bu4NPF6. The protocol allows for an easy access to tetrahydrofurans bearing a versatile alkyne substituent at the quarternary 2-position under very mild reaction conditions.

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Source
http://dx.doi.org/10.1021/ol400809nDOI Listing

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