Please join Yale Chemistry for a thesis seminar with Jihyeon Yeo, Ellman Lab.
Title: Co(III)-Catalyzed Sequential C–H Bond Additions to Dienes and One-Carbon Electrophiles and [3 + 2] Cycloaddition of Sulfoxonium Ylides With Alkenes
Summary: The first part of my dissertation focused on the modular synthesis of complex molecules via activation of the C(sp2)–H bond, followed by the addition of two different coupling partners in a selective order. Two reactions using Earth-abundant cobalt(III) catalysts were developed, both involving sequential C–H bond addition to unactivated 1,3-dienes and one-carbon electrophiles. These methods also demonstrated difunctionalization of internally substituted dienes via uncommon 1,3-addition to form two new C–C bonds and furnish synthetically challenging all-carbon quaternary centers. Various synthetic transformations were performed on the final products to substantiate their utility, and the mechanistic studies provided further insights into the reactions.
The second part of my dissertation is based on a serendipitous discovery during an investigation of a novel sequential C–H bond addition transformation. A practical diastereoselective approach was developed to access various substituted cyclopentanones via [3 + 2] cycloaddition of sulfoxonium ylides with alkenes.
