Nomenclature of organometallic compounds of the transition elements (IUPACRecommendations 1999)

Organometallic compounds are defined as containing at least one metal-carbo n bond between an organic molecule, ion, or radical and a metal. Organometa llic nomenclature therefore usually combines the nomenclature of organic ch emistry and that of coordination chemistry. Provisional rules outlining nom enclature for such compounds are found both in Nomenclature of Organic Chem istry, 1979 and in Nomenclature of Inorganic Chemistry, 1990. This document describes the nomenclature for organometallic compounds of th e transition elements, that is compounds with metal-carbon single bonds, me tal-carbon multiple bonds as well as complexes with unsaturated molecules ( metal-pi-complexes). Organometallic compounds are considered to be produced by addition reaction s and so they are named on an addition principle. The name therefore is bui lt around the central metal atom name. Organic ligand names are derived acc ording to the rules of organic chemistry with appropriate endings to indica te the different bonding modes. To designate the points of attachment of li gands in more complicated structures, the eta, kappa, and mu-notations are used. The final section deals with the abbreviated nomenclature for metallo cenes and their derivatives.