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This study examines the intrinsic structural and optoelectronic properties of the neutral indeno[1,2-b]fluorene skeleton as well as those of the corresponding anion radical and dianion. We report their characterization by analysis of solid-state structures and EPR, NMR, and absorbance spectra. Additionally, 20 popular density functional theory methods are used to evaluate their performance for predicting NMR chemical shifts, EPR hyperfine coupling constants, and low-energy transitions of the absorbance spectrum to act as a guide for future studies. This information can be used for a better understanding and tuning of the electron-transporting/accepting ability of the indenofluorene core for use in organic photovoltaics and organic field effect transistors.

Two new rubidium salts of the bowl-shaped corannulene monoanion radical C20H10•– (1•–), [Rb(15-crown-5)2+][C20H10–] (2) and [Rb(dicyclohexano-18-crown-6)+][C20H10–] (3), have been synthesized and structurally characterized in this work. An excess of 15-crown-5 ether provided full encapsulation of the rubidium ion in [Rb(15-crown-5)2]+, which precluded metal-directed π interactions with the anionic surface of C20H10•– in the solid-state structure of 2. The use of more sterically demanding dicyclohexano-18-crown-6 ether prevented the formation of polymeric chains previously seen with 18-crown-6 ether and favored the isolation of the discrete contact ion pair 3. Complex 3 is built on a convex η6 coordination of Rb+ to C20H10•–, reaffirming the exo-binding preference of rubidium ions toward the singly charged corannulene bowl. A rubidium salt of the planar coronene monoanion radical C24H12•– (4•–), [Rb(18-crown-6)+][C24H12–] (5), has also been prepared and structurally characterized to reveal a new binding mo...

Mono-, di- and tetraanions of rubrene, (C42H28, Rub0), were generated by the controlled reduction of neutral polyarene with various alkali metals in the appropriate solvent. The X-ray diffraction studies of the resulting adducts of Rub1–, Rub2– and Rub4– with alkali-metal ions revealed the distortion of the rubrene core upon the stepwise acquisition of electrons. Coordination of the Cs+ ion and a noticeable deformation of Rub1– are observed at the first reduction step. Two types of rubrene dianions showing an essentially different conformation and coordination environment for the central tetracene core have been seen in the cesium adduct of Rub2–. Various types of supramolecular assembly between the tetrareduced rubrene anion, Rub4–, and lithium or rubidium cations have been found in the corresponding products in the solid state. The structures of rubrene anions and their aggregation with alkali-metal ions in solution have been studied by ESR and multinuclear NMR (1H, 13C, 7Li and 133Cs) spectroscopy.

Single-crystal X-ray diffraction studies of two polyaromatic radical anions crystallized as sodium salts, namely [Na(DME)(3) ](+)[C(20) H(10)(-)] (1) and [Na(DME)(3)](+)[C(24)H(12)(-)] (2) are reported. This allowed the first structural evaluation of Jahn-Teller (JT) effects for monoreduced circulenes and a comparison between bowl-shaped corannulene and planar coronene. The C(s) and D(2h) symmetrical distortions are found to fit the experimental data for C(20)H(10)(·-) and C(24)H(12)(·-), respectively. The continuous symmetry measure (CSM) analysis was carried out to provide a quantitative measure of the JT distortions in 1 and 2. In addition, the X-ray crystallographic results were fully supported by DFT calculations.

The first successful high-yield solution synthesis of homobimetallic Bi(2)(O(2)CCF(3))(4) (1), as well as heterobimetallic BiRh(O(2)CCF(3))(4) (2) and BiRh(O(2)CCF(2)CF(3))(4) (3), complexes is reported. It is based on one-pot reduction reactions starting from Bi(III) and Rh(II) carboxylates and using Bi metal as a reducing agent. The presence of small amounts of diphenyl ether was found to facilitate this reaction, most probably because of its good solubilizing and π-stabilizing abilities. The latter is illustrated by the isolation and structural characterization of a π-adduct of 1 with diphenyl ether, [Bi(2)(O(2)CCF(3))(4)·1/2Ph(2)O]. Importantly, the new approach expands to solution the chemistry of Bi(II) that was previously limited to the solid state only. The solution procedure developed for the preparation of heterometallic BiRh(O(2)CCF(3))(4) is now one step shorter and gives the product in excellent yield compared with the previously reported method based on sublimation-deposition technique. It is also performed on a greater scale (~10-20 times) and makes further scale-up feasible, if needed. Moreover, it eliminates the isolation of the hard-to-handle unsolvated Bi(II) trifluoroacetate used earlier as a starting material. A new polymorph of BiRh(O(2)CCF(3))(4) (2) was crystallized from solution in this work. The solution approach was also applied to the synthesis of a new heterobimetallic carboxylate with perfluorinated propionate ligands, BiRh(O(2)CCF(2)CF(3))(4) (3). All products are fully characterized by spectroscopic and single crystal X-ray diffraction methods. Complexes 2 and 3 exhibit similar solid state structures based on heterobimetallic paddlewheel units forming infinite 1D chains through intermolecular Rh···O interactions.