Biological reaction, alcohol carbonyl condensations

Fluoroacetonitrile condenses with carbon disulfide in an interesting aldol-type reaction (Scheme 3.14). The carbanion for ethyl fluoroacetate reacts readily with benzaldehyde in a cross-aldol reaction to give the fluorinated alcohol. a-Fluorinated carbonyl compounds are often very toxic materials because biologically they are converted into fluoroacetate, which is toxic to the Krebs cycle. Thus, extreme care is needed during the use of these compounds. 

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