Date : 2013. 11. 21, 4:30 PM Place : Int"l Rm.103, Bldg.25-1 -Abstract- Heterocyclic compounds represent among the most important classes of compounds owing to their unique properties including pharmacological activities, novel properties as new materials for organic solar cells, conducting polymers and molecular electronics. The rapid rise in demand for this class of compounds continues to stimulate the development of new synthetic methods. In this seminar, two different strategies will be discussed. Strain-driven ring expansion is a powerful strategy for construction of various types of elaborate cyclic compounds. We have developed several highly efficient tandem reactions for the synthesis of various heterocycles. Our approach utilizes reactive species such as carbenes and nitrenes to build small size rings and subsequent rearrangement to desired heterocycles. C-H bond activation offers a great promise for the challenges that chemical research and manufacturing industry face as the concerns over environmental impact and limited natural resources draw more attention. Transition metal-catalyzed C-H bond activation features the advantages including catalytic nature of the reactions, obviating pre-functionalization of reactants and broad functional group tolerability. As such, together with our interest in heterocycle synthesis, we have developed a new synthetic method for isoquinolones and pyridones with reverse-regioselectivity.