Abstract
Highly functionalized fluorenones were synthesized by an intramolecular cyclization of 2′′-halo-[1,1′:3′,1′′-terphenyl]-4′-carbonitriles in the presence of
n
-butyllithium or lithium aluminium hydride. The precursor was synthesized by ring transformation of 2-oxo-6-aryl/heteroaryl-4-(
sec.
amino)-2
H
-pyran-3-carbonitriles or 2-oxobenzo[
h
]chromenes with
o
-bromo/chloro/fluoro-acetophenone under basic conditions in moderate yield. We performed the control experiment to understand the proposed mechanism and found that the presence of a secondary amine in the starting material directs the reactivity. The photophysical properties of 3-methoxy-7-(piperidin-1-yl)-5
H
-indeno[2,1-
b
]phenanthren-8(6
H
)-one was explored and solvent dependent emission was observed. These compounds were also tested against HIV-1 and low to moderate activity was observed.