Triphenyl propenone

The first pentalene to be synthesized free of fused rings was the hexaphenyl derivative (752).232) The approach involved fluoride ion-catalyzed Michael addition-Knoevenagel dehydration of 1,2,3-triphenylcyclopentadiene with 1,2,3-triphenyl-propenone and subsequent oxidation with N-bromosuccinimide in CCI4. 

LeGofP treated a mixture of 1,2,3-triphenylcyclopentadiene and 1,2,3-triphenyl-propenone with potassium fluoride in dimethyl sulfoxide and so effected Michael-... 

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