Soluble Catalysts for Improved Pschorr Cyclizations
Frederick W. Wassmundt and William F. Kiesman
*Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060
F. W. Wassmundt, W. F. Kiesman, J. Org. Chem., 1995, 60, 196-201.
Several improved catalysts for the Pschorr phenanthrene synthesis have been discovered; all are soluble substances which initiate free-radical reactions by electron donation and thereby shorten the reaction time and increase the yield. An optimized general procedure with ferrocene in acetone allowed the conversion of various substrates in high yields.
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