Synthesis, physical properties, and anion recognition of two novel larger azaacenes: benzannelated hexazaheptacene and benzannelated N,N'-dihydrohexazaheptacene

Gang Li; Yuechao Wu; Junkuo Gao; Junbo Li; Yang Zhao; Qichun Zhang

doi:10.1002/asia.201300208

Synthesis, physical properties, and anion recognition of two novel larger azaacenes: benzannelated hexazaheptacene and benzannelated N,N'-dihydrohexazaheptacene

Chem Asian J. 2013 Jul;8(7):1574-8. doi: 10.1002/asia.201300208. Epub 2013 Apr 19.

Authors

Gang Li¹, Yuechao Wu, Junkuo Gao, Junbo Li, Yang Zhao, Qichun Zhang

Affiliation

¹ School of Materials Science Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore.

PMID: 23606661
DOI: 10.1002/asia.201300208

Abstract

Two novel larger azaacenes with six or ten N atoms in their backbones, benzannelated 9,11,13,22,24,26-hexazatetrabenzo[a,c,l,n]heptacene (HATBH, 1) and benzannelated 9,26-dihydro-9,11,13,22,24,26-hexaza-tetrapyrido[3,2-a: 2',3'-c: 3'',2''-l: 2''',3'''-n]heptacene (DHATPH, 2), have been successfully synthesized in two steps. The theoretical band gaps estimated through DFT calculations for HATBH (1) and DHATPH (2) are 1.949 eV and 2.278 eV, which are close to the experimentally obtained optical band gaps (2.14 eV and 2.39 eV). Interestingly, HATBH (1) can act as efficient anion sensor for F(-) and H2PO4(-) , while DHATPH (2) selectively responds to F(-) among the ten different anions used (F(-), Cl(-), Br(-), I(-), PF6(-), HSO4(-), NO3(-), BF4(-), AcO(-), and H2PO4(-)). Our synthetic strategy could offer a promising and easy way to obtain even larger azaacenes.