Radical Additions to (η6‐Arene)(tricarbonyl)‐chromium Complexes: Diastereoselective Synthesis of Hydrophenalene and Hydrobenzindene Derivatives by Samarium( II ) Iodide Induced Cyclization

Yes indeed, radical additions to arene-Cr(CO)3 complexes are possible. Treatment of the chiral complex 1 with SmI2 gives tricycle 2 selectively by a 5-endo-trig radical cyclization; dihydro-1 is converted into the demethoxylated complex 3. In the latter case the ketyl radical adds directly to the complexed arene.