Access to [2,1]Benzothiazine <i>S</i>,<i>S</i>-Dioxides from β-Substituted <i>o</i>-Nitrostyrenes and Sulfur
作者:Thi Mo Nguyen、Hoang Anh Cao、Thi Thuong Thuong Cao、Satoki Koyama、Dinh Hung Mac、Thanh Binh Nguyen
DOI:10.1021/acs.joc.0c00918
日期:2020.10.2
[2,1]Benzothiazine S,S-dioxides 2 were synthesized by simply heating o-nitrostyrenes with elemental sulfur in 3-picoline with complete atom economy. This reaction was found to occur without any added catalyst and consist of a cascade of reduction of the nitro group, sulfuration of a C–H of the double bond, oxidation of a sulfur atom to its highest oxidation state by the migration of two oxygen atoms
Iron-catalyzed intramolecular reductive cyclization of o-nitroarenes to indoles under visible light irradiation
作者:Mohd Waheed、Meshari A. Alsharif、Mohammed Issa Alahmdi、Sayeed Mukhtar、Humaira Parveen
DOI:10.1016/j.tetlet.2023.154543
日期:2023.6
An efficient, mild and environmentally benign methodology for the synthesis of indoles via air stable, inexpensive Knölker complexcatalyzedintramolecular reductive cyclization of o-nitrostyrenes at room temperature under photoirradiation has been developed. The stated methodology was capable for a diverse range of o-nitrostyrenes, generates outstanding yields of the indoles.