Terminal methyl as a one-carbon synthon: synthesis of quinoxaline derivatives via radical-type transformation

Abstract

An iron-promoted method for the construction of pyrrolo[1,2-a]quinoxaline derivatives has been developed. Ferric chloride served as a promoter and as a Lewis acid in the reaction. Solvents provided the corresponding carbon sources simultaneously. The majority of solvents with terminal methyl groups, including ethers, amines and dimethyl sulfoxide, were reactive in the synthesis of quinoxaline derivatives at a certain yield via C–H(sp³) amination/C–O or C–N (C–S) cleavage. This method was applicable to a wide range of pyrrolo[1,2-a]quinoxaline and indolo[1,2-a]quinazoline substrates.