Collect. Czech. Chem. Commun. 1994, 59, 499-502

Synthesis of N-Phenylsulfonyl Protected Furo[3,2-b]pyrroles

Vladimír Bobošík and Alžbeta Krutošíková

Department of Organic Chemistry, Slovak Technical University, 81237 Bratislava, Slovak Republic


Protection of nitrogen atom of heterocyclic molecules, such as indole and pyrrole types, enables various reactions of these systems. N-Phenylsulfonyl derivatives, which have been widely used for this purpose, were prepared in the indole series by the reaction of N-sodium and N-lithium salts with benzenesulfonyl chloride. This method requires waterfree and oxygenfree conditions. On the other hand, the phase transfer catalysis conditions used in this work obviates these disadvantages. We therefore selected the latter method for the preparation of variously substituted 4-phenylsulfonylfuro[3,2-b]pyrroles (I - VII) and 1-phenylsulfonylbenzo[b]furo[3,2-b]pyrroles (VIII - IX).