Chemical syntheses green chemistry principle

By measuring the toxicity of all substances used in a given chemical synthesis, we are able to address Green Chemistry Principles 3 (less hazardous chemical synthesis) and 4 (designing safer chemicals). 

The welfare of the people who work with chemical products and processes is at least as important as the welfare of the environment. Green chemistry is anthropocentric (as is sustainable development). Several green chemistry principles reflect this anthropocentrism. Principles 3 (less-hazardous chemical synthesis), 4 (design of safer chemicals), 5 (safer solvents and auxiliaries), and 12 (inherently safer chemistry for accident prevention) express concern for the health of the people who handle materials or attend to processes (Anastas and Warner, 1998). While many of these safety benefits also accrue to nonhuman organisms, the focus of the principles is on the people who are exposed to these materials and methods. Inasmuch as we cannot know all of the environmental needs of nonhuman things, it is hard to imagine how the focus could be on anything else. 

However, the minimization of the risk, both in terms of environment and process safety, could be equally reached by adopting an on-demand synthesis of phosgene and MIC [46]. This is the approach preferred industrially and evidences that the same goal could be reached by a different philosophy, other than the substitution of chemicals indicated by green chemistry principles. 

The need to implement green chemistry principles (e.g., safer solvents, less hazardous chemical synthesis, atom economy, and catalysis) is a driving force toward the avoidance of the use of toxic organic solvents. A solvent-free or solid-state reaction obviously reduces pollution and reduces handling costs due to simplification of experimental procedure and workup technique and savings on labor. However, interest in the environmental control of chemical processes has increased remarkably in the last three decades as a response to public concern about the use of hazardous chemicals. Therefore, to improve the effectiveness of this method in preventing chemical waste, it is important to investigate its optimal conditions. 

So what exactly is green chemistry Green chemistry applies fundamental chemical principles to produce chemical products that are inherently less toxic, either to humans or to the ecosystem, than currently existing chemical products. Green chemistry may be applied to any of the various elements of the chemical product life cycle, from manufacture, to use, and ultimately to disposal. Thus, green chemistry may be applied to the production of a particular chanical to minimize the hazard associated with its use, or it may focus on the manufacture of the chemical to minimize the environmental consequences of the by-products or the synthesis, or it may equally well look into the development of more environmentally friendly alternatives to a specific chemical. Regardless, green chemistry seeks to reduce the hazard associated with chemical species. 

ID S is synthesized by the reaction of ammonia with maleic anhydride in water. The synthesis of EDDS and IDS is also in accordance with the 3rd Principle of Green Chemistry Design Less Hazardous Chemical Synthesis, although they are still not perfectly green as there still some hazardous components. This can be a difficult principle to achieve completely as many reactive chemicals in the chemist s toolbox are often hazardous. 

One of the key principles of green chemistry is the elimination of solvents in chemical synthesis or the replacement of hazardous solvents with environmentally benign solvents. The development of solvent-free alternative syntheses is, of course, the best solution, especially when either one of the substrates or the product is a liquid and can be used as the natural solvent of the reaction. However, if solvents are crucial to a process, we can select from solvents that will have no or limited impact on health and the environment and the selection should be an intrinsic part of green innovation. The most important rule is that we should match the solvent properties with the synthesis objectives and then identify the best available solvent or design a new solvent. 

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