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Bromocyclization of Alkenoic Thioester and Access to Functionalized Sulfur-Heterocycles
Rinako Saegusa1, Takashi Fujihara2, Hiroki Shigehisa1
1Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo, Tokyo 202-8585, Japan.
Abstract:
Although oxygen, nitrogen, and carbon have been extensively studied as nucleophilic elements in the halocyclization of alkenes, sulfur-based nucleophiles are relatively unexplored. Herein, we investigated bromocyclization chemistry involving unsaturated thioesters, with a focus on their use as potential S-nucleophiles. We developed a bromocyclization method that uses alkenoic thioesters and N-bromoacetamide (NBA) to form cyclic bromosulfides. The resulting 5-exo products are labile and can be used in various nucleophilic substitution reactions.
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