title: Iodoalkyne-Based Catalyst-Mediated Activation of Thioamides through Halogen Bonding.
abstract: Halogen bonding catalysis has recently gained increasing attention as a powerful tool to activate organic molecules. However, the variety of the catalyst structure has been quite limited so far. Herein, we report the first example of the use of an iodoalkyne as a halogen bond donor catalyst. By using an iodoalkyne bearing a pentafluorophenyl group as a catalyst, thioamides were efficiently activated and reacted with 2-aminophenol to generate benzoxazoles in good yield. Mechanistic studies, including13C NMR spectroscopic analysis and several control experiments, provided concrete evidence that this catalytic activation is based on halogen bonding. Thus, the results obtained in this study demonstrate that iodoalkynes can serve as a new scaffold for future development of halogen bonding catalysis.
authors: Department of Synthetic Medicinal Chemistry, Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo, 142-8501, Japan. a-matsuzawa@hoshi.ac.jp.
authors: Akinobu
authors: A
authors: Matsuzawa
authors: Department of Synthetic Medicinal Chemistry, Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo, 142-8501, Japan.
authors: Shiho
authors: S
authors: Takeuchi
authors: Department of Synthetic Medicinal Chemistry, Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo, 142-8501, Japan. k-sugita@hoshi.ac.jp.
authors: Kazuyuki
authors: K
authors: Sugita
keywords: halogen bonds; heterocycles; iodoalkynes; organocatalysis; thioamides