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Published on: May 21, 2019
Allenyl azide cycloaddition chemistry. photochemical initiation and CuI mediation leads to improved regioselectivity
Ken S Feldman1, D Keith Hester, Carlos Silva López
1Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA. ksf@chem.psu.edu
Abstract:
Irradiation of 2-(3-alkenyl)allenylphenyl azides in the presence of excess CuI furnished functionalized 2,3-cyclopentenylindoles in good yield with only trace amounts of competitive C-N-bonded regioisomeric products. These results represent a significant departure from the modest-to-nonexistent regioselectivity that attended thermal cyclization of these allenyl azide substrates.
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