Reactivity of pyrene dianion and some of its 2‐substituted derivatives

Abstract

Abstract. The dianion of pyrene in THF reacts with 1 equivalent of a hard electrophile [H' or (CH,),SiCl] at posiiion 1 and with a second equivalent at position 9. 1-And 4-(trimethylsily1)pyrene and 1,9-bis(trimethylsilyl)pyrene have been thus prepared. In THF/NH, , the dianion of pyrene is converted into 1-hydropyrene monoanion by abstraction of a proton from ammonia. From 2-methoxypyrene and 2-tert-butylpyrene dianion, two different monoanions can be formed: protonation is possible at positions 1 and 6. The monoanions have been prepared and alkylated with sodium iodoacetate. Product analysis shows that the 2-tert-butyl-1-and -6-hydropyrene monoanions are formed in the ratio of 6/4, while the 2-methoxypyrene dianion is protonated exclusively at position 1. The results are in agreement with the charge distribution in the dianions of these 2-substituted pyrene derivatives.