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Iridium-Catalyzed C-H Borylations: Regioselective Functionalizations of Calix[4]arene Macrocycles
Gabriele Giovanardi1, Silvia Cattani1, Davide Balestri1
1Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy.
Abstract:
We report iridium-catalyzed C-H borylations for the regioselective synthesis of distally disubstituted calix[4]arene macrocycles. The atom- and step-economical method led to a broad family of calix[4]arenes in good yields and functional group tolerance. The synthetic utility of the C-H borylation protocol was finally illustrated with several late-stage modifications for the synthesis of elaborate calix[4]arenes frameworks, otherwise challenging to achieve with commonly employed procedures.
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