Organic Chemical Technology Research Group of the Hungarian Academy of Sciences, Budapest University of Technology and Economics, H‐1521 Budapest, PO Box 91, Hungary
Abstract:
Valuable new synthetic intermediates, 5(6)‐(chloromethyl)benzimidazoles, were prepared by the facile elimination of sulfur dioxide under the influence of thionyl chloride from benzimidazole‐5(6)‐methane‐sulfonic acids easily obtained from (3,4‐diaminophenyl)methanesulfonic acid with formic‐, or trifluoroacetic acid. Both reaction steps involved only acidic conditions, thus the synthesis of polysubstituted 5(6)‐(chloromethyl)benzimidazoles incorporating base‐sensitive substituents became possible.
