The Unexpected Formation of 9,9,10,10-Tetrafluoro-1,2,4,12-tetraphenyl[2.2]paracyclophan-1-ene

An investigation of the palladium-catalyzed Kumada cross-coupling reaction between PhMgBr and (pseudo-ortho) 4,12-diiodo-1,1,2,2,9,9,10,10-octafluoro[2.2]­paracyclophane revealed that in addition to the expected cross-coupled product, an unintended major product was generated. The product was determined to be 9,9,10,10-tetrafluoro-1,2,4,12-tetraphenyl[2.2]­paracyclophan-1-ene by X-ray crystallography and is proposed to be formed via the first reported example of reductive defluorination by a Grignard reagent.