Group nucleophilic Fukui function

It is also interesting to examine the effect that the electron-releasing groups may have on the local electrophilicity pattern in ethylene 29. These systems have some importance in the IED processes. Consider for instance the electron-rich ethylenes 33 and 35. On the basis of the Fukui function alone, methyl vinyl ether 33 shows nucleophilic activation at the C2 carbon, fk = 0.470. Dimethylvinylamine 35, on the other hand, displays a similar local reactivity pattern, fk = 0.411. Note that on the basis of the to index, both compounds are predicted as marginally electrophilic. Both compounds 33 and 35 are... 

Paquette s early attempts to arrive at a suitably functionalized pyranfocused on gaining access to the dithiane 53 whose role it was to provide a nucleophilic site at C9. The substructure of 53 was recognized to correspond well from the functionality and stereochemistry standpoints to the pattern resident in Fukui s lactone (49), which is readily available from L-malic acid. To enable proper structural modification, the hydroxyl group in 49 was first masked as the PMB ether by implementation of the trichoroacetimidate process (Scheme 15.5). 

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