The contemporary synthetic recipes to access versatile quinoline heterocycles

The synthesis of quinoline (C9H7N) and its derivatives attracted the attention of various research communities due to their prominent roles in medicinal chemistry, coordination chemistry and material chemistry. Because of the requirement for accessing them on an industrial scale, large numbers of chemist efforts are devoted to developing various synthetic methods to obtain these versatile heterocycles in a cost-effective and environmentally supportive manner. This review will summarize the different conventional methods of synthesis of quinolines, and also entrenching special technique approaches such as Microwave-Assisted Organic Synthesis (MAOS), multicomponent reactions, solvent-free reaction conditions, ionic liquids (IL’s), ultrasound-promoted synthesis, phase-transfer catalyst (PTC), photo-catalyst, heterogeneous, homogeneous, and biocatalysis.