Alternative reagents, Green Chemistry

Additionally, the environmental issue of utilizing waste cellulosic material and waste biomass products should be considered as an alternative green chemistry application to the production of many value added products. The combinatorial utilization of carbohydrate scaffolds based on chiral building block functionalization will also constitute attractive and relatively cheap starting materials. This rich selection of potential approaches, combined with further developments of new procedures and modem reagents, creates an enormous opportunity for the field to be at the frontier for many years to come. 

Green chemistry offers the scientific option to deal with the problems associated with hazardous substances. An example is the alternative synthesis of polycarbonate, a polymer that has been commercially produced by the polycondensation between bisphenol-A and phosgene. The traditional synthesis is shown in Figure 12.2. Because phosgene is highly poisonous, a safer option is to use diphenyl carbonate as a non-toxic carbonylation reagent. See Figure 12.3 (Anastas and Williamson, 1996). 

Keywords Green chemistry alternative feedstocks benign reagents catalytic synthetic pathways natural processes biocatalysis alternative solvents safer chemicals alternative reaction conditions minimization of energy consumption... 

SECTION 18.5 The green chemisiry initiative promotes the design and application of chemical products and processes that are compatible with human health and that preserve the environment The areas in which the principles of green chemistry can operate to improve environmental quality include choices of solvents and reagents for chemical reactions, development of alternative processes, and improvements in existing systems and practices. 

A "green chemistry" alternative to the Grignard reaction was introduced in Experiment 36. This was the preparation of an organozinc reagent that was then allowed to react with a carbonyl compound. The reaction results in the formation of a new... 

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