Preparation of benzoxazoles and benzothiazoles utilizing naturally occurring copper-containing mineral catalyst precursors. (17th February 2023)

• Record Type: Journal Article
• Authors: Györke, Gábor; Dancsó, András; Volk, Balázs; Hunyadi, Dávid; Szalóki, Imre; Bulátkó, Anna; Milen, Mátyás
• Is Part Of: Tetrahedron letters. Volume 116(2023)
• Publication Date: 2023-02-17
• Subjects: Catalysis -- Benzoxazoles -- Benzothiazoles -- Ring closure reaction -- Copper-containing minerals; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2022.154319
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Abstract: Copper is one of the most abundant metals on Earth, and although it is mainly used in other fields, copper catalysis is also widely used in preparative organic syntheses. As copper production has recently exceeded a yearly amount of 20 million tons, using minerals instead of pure copper compounds can lower the need for such processes and can lead to more economical and environmentally friendly procedures. Such a method is the subject of our present study in which the preparation of 2-substituted benzoxazoles and benzothiazoles is presented from inexpensive starting materials in a simple setup, in the presence of naturally occurring copper-containing minerals. A total of 7 readily available minerals were tested in our model reaction and the reaction was feasible with all of them. With our method, a wide variety of benzoxazoles and benzothiazoles were prepared in good yields and high purity. The reaction could be carried out regardless of the origin of the minerals.