Ch3o2c

• Avoids hard-to-make o-cyanobenzoates • Avoids liberation of hydrogen cyanide • Reduces number of steps to four from six

FIG. 3.6.3 Databases to improve synthetic schemes. (Reprinted, with permission, from Molecular Design.)

ward from the target to the candidate starting materials. Other programs are synthetic—that is they identify side reactions, by-products, and the effect of various conditions on reaction outcomes. However, none of these programs are built with environmentally benign synthesis in mind.

Out of about twenty software tools examined by J. Dirk Nies (Chemical Information Services, Oakville, Maryland) and colleagues, three programs appear to be useful for providing theoretical alternative synthesis pathways in support of EPA pollution prevention initiatives: Cameo, which operates synthetically, and Syngen and Lhasa, which both operate retrosynthetically. The user, however, must decide which pathways are environmentally safer by considering the health and environmental hazards of the starting reagents (Illman 1993).

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