Stereochirotopomutation nonrotative

Next, we consider examples of stereochirotopomutation - nonrotative (Class 5A) and rotative (Class 5B). In examples 73-78 (Figure 18.14, p. 121), we note that topomutations are only in atoms of type s - equal numbers of atoms type s are destroyed and generated, and there are no alterations in atoms of type o. It should be emphasized that in looking at atoms of type s, one considers only the ones that undergo bond cleavages and/or changes in hybridization vide supra). 

Lastly, stereochirotopomutation is subgrouped into nonrotative stereochirotopomiitation (Class 5A) and rotative stereochirotopomutation (Class 5B). Each of these subclasses can be stereoaselective, nonstereoselective or stereoselective, as well. 

Nonrotative astereochirotopomutation (Class 3A) is indicated for h2 (achiral reagents), and the rotative mode (Class 3B), for h2, h4 (chiral reagents) and h5 (achiral or chiral reagents). Nonchirotopomutation is anticipated for all hi-h6 classes - hi with achiral reagents, h2-h6 with achiral or chiral reagents. No nonrotative stereochirotopomutation (Class 5A) is expected for any of the hl-h6 classes however, rotative stereochirotopomutation (Class 5B) is anticipated only for the he class (chiral reagents). 

Astereochirotopomutations (Classes 3A and 3B) are not indicated with either achiral or chiral reagents. Nonchirotopomutation (Classes 4A and 4B) and stereochirotopomutation (Classes 5A and 5B) are, however, observed - nonrotative modes, with achiral reagents, and rotative variants, with chiral reagents. 

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