This is an advanced course meant for M.Phil level students during first semester. It is a special segment of organometallic chemsitry wherin the metallic part specifically comprises of transiton metals only. The organic part may range from sigma bond to pi bonded hydrocarbons with localized or delocalized elelctron density. The nature of bonding in metal-carbon bond is of main focus. Special emphasis is on η2 to η7 hydrocarbons bonded ot metals. Synthesis, properties and nature of bonding in pi complexes is explored in it. Other topics include experimental tehniques used in synthesis and characterization. Fundamental process in organometallics synthesis; applications of organometallics in medicines and industry.