One-Pot Silylation-Amination Synthesis of 3‑N‑Substituted Benzo[d]isothiazole 1,1-Dioxides
Guilherme Arraché Gonçalves1, Lídia Klatt Oliveira1, Mauro Neves Muniz1
1Instituto Nacional de Ciência e Tecnologia em Tuberculose, Centro de Pesquisas em Biologia Molecular e Funcional, Pontifícia Universidade Católica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil.
Abstract:
An alternative silylation-amination route for the synthesis of 3-N-substituted benzo-[d]-isothiazole 1,1-dioxides is presented. These saccharin-based scaffolds have attracted increasing interest in medicinal chemistry, particularly as potential modulators of hypoxia-inducible factor-2. The preparation of such structures is often associated with chlorination-amination approaches, which suffer from operational drawbacks, the use of chlorinating reagents, and variable efficiency. Herein, we report a one-pot silylation-amination protocol employing hexamethyldisilazane as the silylating agent. The method is operationally simple, applicable to a broad substrate scope, and affords the desired products in moderate to excellent yields (31-99%) under solvent-free conditions.
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