Green synthesis process safety

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 carbamate was converted to 2 using a stoichiometric amount of NaH (which is associated with safety concerns) and (J )-quinuclidin-3-ol. Despite using more than one equivalent of the expensive (J )-quinuclidin-3-ol, the transformation was found to be low yielding, as a substantial amount of unreacted starhng material was recovered and the isolation became cumbersome. Thus the process cannot be regarded as green, and the development of an eco-friendly and catalytic synthesis for solefinacin (2) is warranted. 

At least one of the 12 principles—number 2, design safe products—is a must for pharmaceutical synthesis. Indeed, pharmaceutical products are regulated and tested for safety. Principle number 7, maximize atom economy, refers to a metric against which the greenness of a process may be evaluated. Green metrics are covered in the next section. 

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. 

Green Biocatalysts for Production of Atorvastatin Codexis, Inc. has developed an enzyme-based process that has greatly improved the yield, efficiency, and safety record for manufacture of atorvastatin, the key building block for Lipitor , one of the world s best-selling drugs, that lowers cholesterol by blocking its synthesis in the liver. The new enzymatic process is dramatically faster and more efficient than previous methods, and also reduces cyanide-related waste, the use of solvents, and the need for purification equipment. 

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