Synthesis of a,P-Unsaturated Esters Using the Wittig Reaction

SYNTHESIS OF a,p-UNSATURATED ESTERS USING THE WITTIG REACTION 

Wittig Reagent Containing an Ester EWG, a Stabilized Ylide 

While the Wittig reaction typically gives the (Z)-alkene as the major product, stabilized ylides usually give the ( ) stereoisomer. 

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