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Updated: Aug 19, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Microwave-assisted "libraries from libraries" approach toward the synthesis of allyl- and C-cyclopropylalkylamides
Peter Wipf1, Claire M Coleman, Jelena M Janjic
1Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA. pwipf@pitt.edu
Abstract:
Cascade reactions of internal and terminal alkynes, zirconocene hydrochloride, dimethylzinc, and phosphinoyl imines (prepared in one step from aldehydes and diphenylphosphinoyl amide) lead to allylic phosphinoyl amides after aqueous workup. Microwave acceleration allows the completion of this one-pot reaction sequence in 10 min. These allylic amides can be converted into a variety of derivatives, including carbamates and sulfonamides, or reacted prior to workup with diiodomethane to give novel C-cyclopropylalkylamides. A solution-phase "libraries from libraries" approach was used to generate an intermediate 20-member library which was subsequently expanded to a 100-member library by a series of N-functionalizations. The biological activity was evaluated in an assay for competitive binding to the estrogen receptor (ERalpha), revealing three potent lead compounds of a new structural type.
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