In process chemistry

Frequently a piece of equipment is used in different processes during its lifecycle. This could result in process conditions that exceed the safe operating limits of the equipment. Equipment inspection may provide a poor prediction of the equipment s useful life and reliability, due to the change of material handled or change in process chemistry over the life of equipment. Batch operations are also characterized by frequent start-up and shut-down of equipment. This can lead to accelerated equipment aging and may lead to equipment failure. This chapter presents issues and concerns related to the safe design, operation, and maintenance of various pieces of equipment in batch reaction systems, and provides potential solutions. 

Equipment inspec- Reevaluate and possibly reset inspection intervals tion may provide a when equipment is used for handling different poor prediction of chemistry equipment safety, Perform management of change review due to change of material handled or change in process chemistry over the life of equipment. ... 

Basic process chemistry using less hazardous materials and chemical reactions offers the greatest potential for improving inherent safety in the chemical industry. Alternate chemistry may use less hazardous raw material or intermediates, reduced inventories of hazardous materials, or less severe processing conditions. Identification of catalysts to enhance reaction selectivity or to allow desired reactions to be carried out at a lower temperature or pressure is often a key to development of inherently safer chemical synthesis routes. Some specific examples of innovations in process chemistry which result in inherently safer processes include ... 

Mueller, R.H., A Practical Synthesis of Ifetroban Sodium. In Process Chemistry in the Pharmaceutical Industry (K.G. Gadamasetti, ed.). Chap. 3, Marcel Dekker, Inc., New York, 1999, pp. 37-55. 

Blagden, N., and Davey, R., Polymorphs take shape, Chem. in Brit., March 1999, p. 44. Owen, M., and Dewitt, S., Laboratory Automation in Chemical Development. In Process Chemistry in the Pharmaceutical Industry (K.G. Gadamasetti, ed.), Marcel Dekker, Inc., New York 1999, pp. 429-455 Conner, K., The drive to improve the bottom line. Today s Chemist at Work, November 1999, p. 29. Sullivan, M., Automation accelerates synthesis. Today s Chemist at Work, September 1999, p. 48. Studt, T., Raising the bar on combinatorial discovery, Drug Discovery Development, January/February 2000, p. 24. Harness, J.R., Automated sample handling supports synthesis and screening. Drug Discovery Development, January 1999, p. 69. 

In Chapter 1, John Lowe details The Role of Medicinal Chemistry in Drug Discovery in the twenty first century. The overview should prove invaluable to novice medicinal chemists and process chemists who are interested in appreciating what medicinal chemists do. In Chapter 2, Neal Anderson summarizes his experience in process chemistry. The perspectives provide a great insight for medicinal chemists who are not familiar with what process chemistry entails. Their contributions afford a big picture of both medicinal chemistry and process chemistry, where most of the readers are employed. Following two introductory chapters, the remainder of the book is divided into three major therapeutic areas I. Cancer and Infectious Diseases (five chapters) II. Cardiovascular and Metabolic Diseases (six chapters) and III. Central Nervous System Diseases (four chapters). 

When a molecule is selected as a potential new drug and enters the development phase a key requirement is for the task of staff in Process Chemistry (Chemical Development) to quickly and safely prepare supplies of the compound to fund... 

Despite the area of microwave-assisted chemistry being 20 years old, the technique has only recently received widespread global acceptance. This is a consequence of the recent availability of commercial microwave systems specific for synthesis, which offer improved opportunities for reproducibility, rapid synthesis, rapid reaction optimisation and the potential discovery of new chemistries. The beneficial effects of microwave irradiation are finding an increased role in process chemistry, especially in cases when usual methods require forcing conditions or prolonged reaction times. 

In process chemistry terms, change is a continuum. Discoveries and their development lead to processes that give higher yields, create cost reduction, introduce... 

Vaidyanathan, R. In Process Chemistry in the Pharmaceutical Industry, Ed. Braish, T. and Gadamasetti, K. CRC Press, Boca Raton, FI, 2008,49-63. 

Reactive hazard evaluations should be made on all new processes as well as existing processes on a periodic basis. There is no substitute for experience, good judgement, and good data when evaluating potential hazards. Reviews in process chemistry should include (a) reactions, (b) side reactions, (c) heat of reaction, (d) potential pressure buildup, and (e) intermediate streams. Reactive chemicals test data should be reviewed for evidence of flammability characteristics, exotherms, shock sensitivity, or other evidence of instability. Examine Planned operation of the process should be examined, especially for... 

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