The enamines from cyclopropyl-methyl-,-ethyl-and-cyclopentylketone have been prepared by reaction of the ketone with a secondary amine and TiCl4. Their vinylcyclopropane structure has been demonstrated by NMR. The reaction of dicyclopropylketone, cyclopropylphenylketone or cyclopropyl-α-thienylketone with secondary amines and TiCl4 afforded homoallylic rearrangement products, namely 1-cyclopropyl-, 1-phenyl-and 1-(α- ...