Organotransition-metal chemistry: past development and future outlook

The course of the development of organometallic chemistry is reviewed from the author's personal viewpoint. The impact of the discoveries of ferrocene and the Ziegler catalyst on the later development of organotransition-metal chemistry is discussed. Through evolution of fundamental concepts, such as the insertion of olefins and carbon monoxide into metal—carbon bonds, oxidative addition and reductive elimination, and attack of nucleophiles on coordinated ligands, together with reactivities of carbene and metallacyclic complexes, various important processes have been developed. The diversity of transition-metal complexes and their unique reactivities not found in usual organic compounds warrant further developments in the various forefronts related to organometallic chemistry with almost limitless possibilities in applications as well as in fundamental studies.