A Case Study Peterson Olefination

Trimethyl(trifluoromethyl)silane (Me3SiCF3), commonly referred to as the Ruppert-Prakash reagent, serves as a trifluoromethyl anion equivalent, which is remarkable because of the instability of the anion with respect to decomposition to difluorocar-bene and fluoride  

The reagent works well for a variety of carbonyl compounds, both aldehydes and ketones  

The reaction depends on a fluoride ion source such as cesium fluoride or TBAF as catalyst. Provide a mechanistic rationale for the transformation, as well as for the catalytic role of fluoride. 

In Peterson olefination, an a-silylcarbanion is reacted with a carbonyl compound to give a / -hydroxysilane, after mild acidic work-up (e.g., with aqueous NH4CI)  

Under basic conditions, the alkoxide derived from the -hydroxysilane eliminates silanolate to form an olefin  

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