6,12-Diarylindeno[1,2-b]fluorenes: Syntheses, Photophysics, and Ambipolar OFETs

Abstract

Herein we report the synthesis and characterization of a series of 6,12-diarylindeno[1,2-b]fluorenes (IFs). Functionalization with electron donor and acceptor groups influences the ability of the IF scaffold to undergo two-electron oxidation and reduction to yield the corresponding 18- and 22-π-electron species, respectively. A single crystal of the pentafluorophenyl-substituted IF can serve as an active layer in an organic field-effect transistor (OFET). The important finding is that the single-crystal OFET yields an ambipolar device that is able to transport holes and electrons.

Recent Progress in Quinoidal Singlet Biradical Molecules

“…Actually, the 1 H NMR spectrum of 36 shows sharp signals in the aromatic region and the optically determined HOMOLUMO gap is relatively large (1.98 eV). Aryl-substituted derivatives were also prepared and field-effect transistor (FET) characteristics were measured for a single crystal 77 or thin-films. 78 The field-effect hole and electron mobilities of the 6,12-bis(pentafluorophenyl) derivative were 7 © 10 ¹4 and 3 © 10 ¹3 cm 2 V ¹1 s ¹1 in the single crystal state, respectively.…”

Unusually short excited state lifetimes of indenofluorene and fluorenofluorene derivatives result from a conical intersection

“…Numerous small-molecule systems have been developed toward this goal that employ extended pi-conjugated centers [5][6][7][8][9]. One such molecular class of interest is the p-quinodimethane-containing indenofluorenes and related molecules (e.g., 1-3, Figure 1), which have recently been realized through synthesis [10][11][12][13][14][15][16][17]. Intriguingly, these compounds have been found to be non-emissive and thus we wished to examine their photophysics.…”

A theoretical study of substituted indeno[1,2-b]fluorene compounds and their possible applications in solar cells

“…The donor substituents used correspond to phenyl [25,31,32], amine and methyl, while acceptor substituents correspond to nitro, cyanide and chloride, arranged according to the strength of their electron acceptor/withdrawing effect, related with the Hammett constants, see Figure 4 and Table 1. All substitutions were carried out at the 6,12-positions on the molecule according with the analysis of the HOMO and the Fukui function of the indenofluorene.…”