Deprotonation-induced aromaticity enhancement and new conjugated networks in meso-Hexakis(pentafluorophenyl)[26]hexaphyrin.
meso-Hexakis(pentafluorophenyl)-substituted neutral hexaphyrin with a 26π-electronic circuit can be regarded as a real homolog of porphyrin with an 18π-electronic circuit with respect to a quite flat molecular structure and strong aromaticity. We have investigated additional aromaticity enhancement of meso-hexakis(pentafluorophenyl)[26]hexaphyrin(1.1.1.1.1.1) by deprotonation of the inner N-H groups in the macrocyclic molecular cavity to try to induce further structural planarization. Deprotonated mono- and dianions of [26]hexaphyrin display sharp B-like bands, remarkably strong fluorescence, and long-lived singlet and triplet excited-states, which indicate enhanced aromaticity. Structural, spectroscopic, and computational studies have revealed that deprotonation induces structural deformations, which lead to a change in the main conjugated π-electronic circuit and cause enhanced aromaticity.
Department of Chemistry, Yonsei University, Seongsanno, Seodaemun-gu, Seoul, Korea.
Won-Young
WY
Cha
Jong Min
JM
Lim
Min-Chul
MC
Yoon
Young Mo
YM
Sung
Byung Sun
BS
Lee
Sho
S
Katsumata
Masaaki
M
Suzuki
Hirotaka
H
Mori
Yoshiya
Y
Ikawa
Hiroyuki
H
Furuta
Atsuhiro
A
Osuka
Dongho
D
Kim