Cyclophane-Type Fullerene-dibenzo[18]crown-6 Conjugates withtrans-1,trans-2, andtrans-3 Addition Patterns: Regioselective Templated Synthesis, X-Ray Crystal Structure, Ionophoric Properties, and Cation-Complexation-Dependent Redox Behavior

Origin of the Open Circuit Voltage of Plastic Solar Cells

“…Recently, qualitatively comparable results with respect to increasing the electron affinity of fullerenes were obtained with isoxazolo-fullerenes, [19] fulleropyrrolidium salts, [20] and certain metal containing fullerene-crown ether conjugates. [21] The possible application of fullerene derivatives in an organic ªplasticº solar cell, however, demands processability and a total reversibility of the one-electron reduction. These criteria are met by both azafulleroid 5 and ketolactam 6.…”

Tether-directed remote functionalization of fullerenes C60 and C70

“…Addition of KPF 6 to the reaction mixture led to an enhanced yield (50%) and regioselectivity (only trans-1) through an additional template effect originating from the complexation of K + ions by the ionophore which reduces its conformational flexibility [35]. The complex between (±)-14 and KPF 6 was characterized by X-ray crystal-structure analysis which confirmed the close tangential orientation of the ionophore atop the carbon cage.…”

Advanced Optoelectronics Materials by Fullerene and Acetylene Scaffolding

“…A very tedious, multistep synthesis of cis-bisdeprotected TEEs, passing via several unstable intermediates, prevented until recently the preparation of functionalized derivatives of the perethynylated antiaromatic octadehydro [12]-and aromatic dodecadehydro [18]annulenes we had reported more than 10 years ago [68]. A recently developed simple photochemical route now enabled us to prepare and study derivatives 6 and 7, bearing lateral DMA substituents (Fig.…”

“…Only the intensity of the CT band in 7 (ε = 105 200 M -1 cm -1 ) is higher than in 6 (ε = 35 100 M -1 cm -1 ), due to the larger number of donor-acceptor conjugation pathways in 7. We consider these results rather surprising, since one might expect the CT to be more efficient in the [12]annulene as the uptake of electrons reduces the antiaromaticity, whereas in the case of the [18]annulene, the uptake of electrons is accompanied by a loss of aromaticity. Clearly, the nature of these electronic transitions is governed by other factors than aromaticity/antiaromaticity.…”

“…To produce fullerene building blocks for modular construction, we introduced the stereo-and regioselective tether-directed remote functionalization of the carbon spheres, leading to a new chemistry in three dimensions [13][14][15]. Taking advantage of versatile synthetic protocols [16,17], we prepared fullerene-based electrochemical ion sensors [18,19], solid-contact ion-selective electrodes [20], monolayers for photocurrent generation [21], fullerene-coated electrodes [22], fullerene-modified semiconductor surfaces [23], as well as polysiloxane-supported oxidation catalysts [24]. In this review, we describe our research in fullerene-porphyrin scaffolding, leading to molecular systems with unusual photophysical and redox properties and, in a very recent development, to the formation of nanopatterned surfaces by self-assembly.…”