2-Nitrobenzothiophene and 3-Nitrobenzothiophene as Electrophiles in Polar Diels-Alder Reactions. Solvent effects

Abstract

In this work the polar Diels-Alder reactions between 2-and 3-nitrobenzothiophenes derivatives and different dienes such as 2-methyl-1,3-butadiene and 1-trimethylsilyloxy-1,3butadiene are studied. Molecular solvent and protic ionic liquids are employed as reaction media. The presence of a very strong electron-acceptor group such as nitro, improve the electrophilic character of these heterocyclic compounds. Moreover, this substituent is easily extruded under thermal conditions make this reaction sequence a simple method of organic compound families with heteroatom rings preparation.