Authors: Dr. Ekata Singh
Abstract: Organic synthesis uses solvents in nearly every stage of a chemical process. Solvents are very important as they dissolve reactants, enhance mixing, control reaction temperature and make it easier to isolate and purify the final product. Solvents also affect the speed and result of the reaction, in many cases. Solvents are widely used in laboratory research and industrial chemical production. But many of the most commonly used solvents are dangerous. They are toxic, flammable, highly volatile and difficult to dispose of safely. Common examples include benzene, chloroform, dichloromethane, N,N-dimethylformamide (DMF) and N-methyl-2-pyrrolidone (NMP). Long-term or repeated exposure to such solvents may affect skin, lungs, liver, nervous system and in some cases even increase the risk of cancer or reproductive damage. If not managed properly, solvent waste may pollute air, water and soil. As a result of these concerns, chemists are now giving more emphasis to reducing the use of hazardous solvents in organic synthesis. This is one of the central goals of green chemistry. Green chemistry promotes the designing of safer chemical processes that use fewer harmful substances and create less waste. This paper explains why hazardous solvents are widely used in organic synthesis and how they lead to health, safety, and environmental hazards. It also discusses the main green chemistry methods used for the reduction of solvent-related hazards. And this is where we want to see if we can replace hazardous solvents with safer ones, use greener solvents, carry out solvent-free reactions, design better reaction structures and recover or recycle solvents after use when we want to. Some good things have been done so far but a lot of scientific and practical problems remain. Still, the right way forward is to reduce the use of hazardous solvents so organic synthesis is safer and cleaner.