Stereoselective Synthesis of Cyclobutanes by Contraction of Pyrrolidines
Chunngai Hui1,2, Lukas Brieger2, Carsten Strohmann2
1Max Planck Institute of Molecular Physiology, Department of Chemical Biology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.
Abstract:
Here we report a contractive synthesis of multisubstituted cyclobutanes containing multiple stereocenters from readily accessible pyrrolidines using iodonitrene chemistry. Mediated by a nitrogen extrusion process, the stereospecific synthesis of cyclobutanes involves a radical pathway. Unprecedented unsymmetrical spirocyclobutanes were prepared successfully, and a concise, formal synthesis of the cytotoxic natural product piperarborenine B is reported.
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