Several reactions taught in Pharmaceutical and medicinal chemistry laboratory today are hazardous to environment and hence needs to be modified. With an impetus from Pollution control act, Green Chemistry; a relatively newer branch has originated. This book discusses the concepts and the implementation of various green chemical reactions. Basic concepts of ionic liquids, organic synthesis and their applications for name organic reactions are discussed. In organic synthesis, ionic liquids have been extensively used for the variety of synthetic transformations. Ionic liquids have been emerging as a versatile class of green solvents with many projected advantages compared with conventional media. In the present book, we would account the synthesis of various kinds of nitrogen heterocycles using variety of ionic liquids too.