A series of fluorene-bridged bisazolium salts L
1
H
2
·X
2
-L
6
H
2
·X
2
(X = Br– or PF6
–) and six related N-heterocyclic carbene silver(I)
complexes [(L1Ag)2](NO3)2 (1), {[L2Ag2(CH3CN)2]2}(PF6)4 (2), [(L3Ag)2(Ag2Br4)]
n
(3), [(L4Ag) (NO3)]
n
(4), [L5Ag2Br2]
n
(5), and [L6(AgCl)2] (6)
have been synthesized and characterized. Each cationic moiety of 1 or 2 contained one 28-membered macrometallocycle
formed via two silver(I) ions and two biscarbene ligands (L
1
for 1 and L
2
for 2). 1D coordination polymeric
chains of 3–5 were formed by different
monomers. The open structure of 6 was formed through
one biscarbene ligand L
6
and
two [AgCl] units, in which two [AgCl] units pointed to opposite directions.
Additionally, the recognition performance of 2 to Cu2+ was researched through fluorescence spectra, UV/vis spectra, 1H NMR titrations, HRMS, IR spectra, and the quantum chemical
computations. The results showed that 2 can effectually
differentiate Cu2+ from other cations.