Regiocontrolled palladium-catalyzed arylative cyclizations of alkynols
Daishi Fujino1, Hideki Yorimitsu, Atsuhiro Osuka
1Department of Chemistry, Graduate School of Science, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan.
Abstract:
Tuning the reactivity of arylpalladium intermediates enables control of catalytic arylative 5-exo and 6-endo cyclizations of alkynols. The two modes of cyclizations represent a rare example of controllable, regioselective difunctionalization of alkynes. The cyclizations are useful in offering a divergent synthesis of oxygen-containing heterocycles, which is of synthetic use for further derivatization. Formal synthesis of an hNK-1 receptor antagonist also showcases the utility of our arylative cyclization.
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