Stereospecific and Stereoselective Rhodium(I)-Catalyzed Intramolecular [2+2+2] Cycloaddition of Allene-Ene-Ynes: Construction of Bicyclo[4.1.0]heptenes
Treatment of the allene‐ene‐yne substrates with [RhCl(CO)2}2] effected the intramolecular [2+2+2]‐type ring‐closing reaction to produce various of tri‐ and tetracyclic derivatives containing a cyclopropane ring. The reaction is highly stereoselective as well as stereospecific with good to excellent yields.