Inter- and intramolecular carbene reactions of diazoketones tethered to tricarbonyliron coordinated acyclic dienes. New tricarbonyliron complexes of cyclohexa-2,4-dienone and cyclopent-2-enone
terminal position have been synthesized, and their decomposition reactions as carbene precursors studied. Intermolecular reactions with nucleophilic olefins were observed with Cu(acac)2 as catalyst, the tricarbonyliron playing the role of an efficient protecting group of the diene fragment. With rhodiumII acetate, intramolecularreactions predominate, with formation of five-membered rings, in the side