Photoirradiation of pyrene in the presence of 1,4-dicyanobenzene and NaCN i
n a benzonitrile/water mixture (1/100, vol/vol%) under vigorous stirring ga
ve 1-cyanopyrene (PyCN) in an 83% yield, while an analogous reaction in ace
tonitrile/water (9/1, vol/vol%) yielded PyCN in a 61% yield.