Hydroalkynylative cyclization of 1,6-enynes with terminal alkynes
Qi Teng1, Nuligonda Thirupathi1, Chen-Ho Tung1
1Key Lab for Colloid and Interface Chemistry of Education Ministry , School of Chemistry and Chemical Engineering , Shandong University , Jinan 250100 , People's Republic of China .
Abstract:
A rhodium-catalyzed highly regio- and enantioselective hydroalkynylation, generating cis-hydrobenzofuranone-tethered enynes has been developed. The reaction proceeds with a selective head-to-head insertion and symmetry breaking Michael addition cascade. One product was produced from tens of possible isomers through precise control of chemo-, regio-, and stereoselectivities using a single rhodium catalyst. Notable features of this method include 100% atom-economy, mild reaction conditions and a very broad substrate scope.
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