Synthesis umpolung strategy

A synthetic route for the synthesis of 2-deoxy-C-aryl glycosides using an umpolung strategy has been reported by Aidhen and co-worker (Scheme 1.7). The synthetic endeavour led to a versatile intermediate aryl ketone 1.13, which has paved the way for two important classes of C-glycosides, i.e. C-alkyl furanosides 1.14 and methyl 2-deoxy-C-aryl pyranosides 1.15. 

These strategies are more difficult to realize with the reagents you have met so far but conjugate addition of a cyanide to an unsaturated carbonyl compound would be an example of the d1 + a3 strategy. We have included these to try to convince you that there is no escape from umpolung in the synthesis of a 1,4-dicarbonyl compound. If you were making this keto-ester you would have to understand two of the three strategies. 

Chapter 1 is devoted to exploring strategies involved in organic synthesis. It seeks to explain concepts like retrosynthetic analysis, atom economy, umpolung approach, click chemistry and asymmetric synthesis. On the basis of interesting and relevant examples, protection and deprotection of different functional groups are explained and the most probable mechanism is also mentioned for important reactions. 

In 2011, Sparr and Gilmour reported an enantioselective strategy for the synthesis of 1,3-dichlorides by a formal umpolung of the y position of conventional... 

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