Preserve ring Subject

Is Cgo aromatic Although it is completely conjugated, it is not planar. Because of its curvature, it is not as stable as benzene. In fact, it undergoes addition reactions with electrophiles in much the same way as ordinary alkenes. Benzene, on the other hand, undergoes substitution reactions with electrophiles, which preserves the unusually stable benzene ring intact. These reactions are the subject of Chapter 18. 

Carbohydrates. Some families of organics, notably monosaccharides, have highly stylized features, such as rings and substituent orientation. These orientations need to be preserved (cleanup) or created (de novo). Fischer and Haworth projections, entirely different alternatives, are also subject to special rules of stereochemistry and chain form. 

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