Abstract Treatment of fluorenone or 4-azafluoren-9-one with 2-pyridyllithium gives 45- hydroxy-5-(2-pyridyl) fluorene and its aza analog. The structure of the former has been studied by x-ray crystallography. It was found that, in contrast to the non-condensed diaryl-2- pyridylcarbinols, these alcohols do not undergo acid catalyzed dehydration and heterocyclization. Under pyrolytic conditions. 5-pyridylfluorenol undergoes fission to form ...