Deprotonation as a Source of Enolate Reactivity

The generation of an enolate (as a C(l) nucleophile) by a deprotonation step was achieved when the alternative mode of enolization towards C(3) was 

In summary, enolates derived from 2-ketosugars may serve as progenitors to C-glycosides, but this topic is still at an early phase of its development and warrants more extensive investigation and evaluation. 

Enolate Reactivity at the Anomeric Site Based on Ester Stabilization 

C-Glycoside synthesis may be achieved in twro ways. Intermolecular radical addition reactions are observed with (i) polarized, electron-deficient alkenes, (ii) alkenes that provide a high level of stabilization to the initial radical adduct and (in) substrates that undergo a facile fragmentation (e.g. allyl stannanes). Additions to less reactive substrates, though not favored for intermolecular processes, are observed if the two components are tethered in an intramolecular array. 

While a full discussion of radical-mediated C-glycoside synthesis is beyond both the space available and the general remit of this chapter, illustrative examples of the nature of the transformations available will be described. Comprehensive reviews are, however, available [3,4] and should be consulted for more detailed accounts. 

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