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A novel buckybowl catcher with an extended π‐surface has been synthesized via cross‐coupling of two bowl shaped bromoindacenopicene moieties with a tolyl linker. The obtained catcher has been unambiguously characterized by 2D‐NMR and mass spectrometry. DFT calculations indicate that the curved shape of the receptor moieties is favourable for binding fullerenes. Effective binding was confirmed for interactions with C60 and C70 utilizing NMR spectroscopy and isothermal titration calorimetry (ITC). The resulting binding values show a higher affinity of the catcher towards C70 over C60. The designed catcher demonstrated the fundamental possibility of creating sensors for spherical aromaticity. [ABSTRACT FROM AUTHOR]

15N‐labeled tetrasulfur tetranitride (S415N4) was synthesized by reacting S2Cl2 with 15NH3. The reaction was finalized with 14NH3. The successful labeling was confirmed by solution 15N nuclear magnetic resonance (NMR) spectroscopy. S415N4 was used for the synthesis of poly(sulfur nitride) S15Nx via the intermediate species of S2N2. It was a topochemical polymerization in the solid state. The isotope ratio in the labeled polymer was obtained by laser deposition ionization time‐of‐flight mass spectroscopy. Solid‐state 15N NMR spectroscopy of S15Nx indicates that at least three different chemical environments for 15N atoms are present in the crystals. Finally, SNx was polymerized in the presence of two other superconductors, MgB2 and yttrium barium copper oxide (YBCO), which demonstrates the capability of SNx for grain boundary engineering. [ABSTRACT FROM AUTHOR]

We investigate the gas-phase chemistry of noncovalent complexes of [10]cycloparaphenylene ([10]CPP) with C60 and C70 by means of atmospheric pressure photoionization and electrospray ionization mass spectrometry. The literature-known [1: 1] complexes, namely [10]CPP⊃C60 and [10]CPP⊃C70, are observed as radical cations and anions. Their stability and charge distribution are studied using energy-resolved collision-induced dissociation (ER-CID). These measurements reveal that complexes with a C70 core exhibit a greater stability and, on the other hand, that the radical cations are more stable than the respective radical anions. Regarding the charge distribution, in anionic complexes charges are exclusively located on C60 or C70, while the charges reside on [10]CPP in the case of cationic complexes. [2: 1] complexes of the ([10]CPP2 ⊃C60/70)+ ⋅/- ⋅ type are observed for the first time as isolated solitary gas-phase species. Here, C60 -based [2: 1] complexes are less stable than the respective C70 analogues. By virtue of the high stability of cationic [1: 1] complexes, [2: 1] complexes show a strongly reduced stability of the radical cations. DFT analyses of the minimum geometries as well as molecular dynamics calculations support the experimental data. Furthermore, our novel gas-phase [2: 1] complexes are also found in 1,2-dichlorobenzene. Insights into the thermodynamic parameters of the binding process as well as the species distribution are derived from isothermal titration calorimetry (ITC) measurements. [ABSTRACT FROM AUTHOR]

We have discovered a dual (i. e., soft and hard) Lewis acidity of alumina that enables rapid one‐pot π‐extension through the activation of terminal alkynes followed by C−F activation. The tandem reaction introduces an acenaphthene fragment – an essential moiety of geodesic polyarenes. This reaction provides quick access to elusive non‐alternant polyarenes such as π‐extended buckybowls and helicenes through three‐point annulation of the 1‐(2‐ethynyl‐6‐fluorophenyl)naphthalene moiety. The versatility of the developed method was demonstrated by the synthesis of unprecedented structural fragments of elusive geodesic graphene nanoribbons. [ABSTRACT FROM AUTHOR]

Herein, we report a new method for synthesis of extended perylenes and terrylenes. The technique is based on the cascade dehydrative π‐extensions (DPEX) of aryl aldehydes, in which stepwise annulations activate previously "dormant" substituents. Two‐ and fourfold cyclizations of 3‐aryl‐biphenyl‐2,2′‐dicarbaldehydes offer a rapid path to unsymmetrical perylenes and elusive terrylene derivatives, respectively. DPEX of 3,3′′‐(phenanthrene‐1,8‐diyl)bis (([1,1′‐biphenyl]‐2,2′‐dicarbaldehyde)) leads to the biradical structure, which proceeds in situ into oxidative electrocyclization at room temperature. The described domino process complements and expands DPEX approach to a large family of fused acenes and related PAHs. [ABSTRACT FROM AUTHOR]

We designed a straightforward synthetic route towards a full‐fledged family of π‐extended helicenes: superhelicenes. They have two hexa‐peri‐hexabenzocoronenes (HBCs) in common that are connected via a central five‐membered ring. By means of structurally altering this 5‐membered ring, we realized a versatile library of molecular building blocks. Not only the superhelicene structure, but also their features are tuned with ease. In‐depth physico‐chemical characterizations served as a proof of concept thereof. The superhelicene enantiomers were separated, their circular dichroism was measured in preliminary studies and concluded with an enantiomeric assignment. Our work was rounded‐off by crystal structure analyses. Mixed stacks of M‐ and P‐isomers led to twisted molecular wires. Using such stacks, charge‐carrier mobilities were calculated, giving reason to expect outstanding hole transporting properties. [ABSTRACT FROM AUTHOR]

The synthesis of pristine non‐planar nanographenes (NGs) via a cyclodehydrofluorination strategy is reported and the creation of highly strained systems via alumina‐assisted C−F bond activation is shown. Steric hindrance could execute an alternative coupling program leading to rare octagon formation offering access to elusive non‐classical NGs. The combination of two alternative ways of folding could lead to the formation of various 3D NG objects, resembling the Japanese art of origami. The power of the presented "origami" approach is proved by the assembly of 12 challenging nanographenes that are π‐isoelectronic to planar hexabenzocoronene but forced out of planarity. [ABSTRACT FROM AUTHOR]

A novel catalyst‐free approach to benzoannulated oxygen‐containing heterocycles from fluorinated oligophenylenes is reported. Unlike existing methods, the presented reaction does not require an oxygen‐containing precursor and relies on an external oxygen source, potassium tert‐butoxide, which serves as an O2− synthon. The radical nature of the reaction facilitates nucleophilic substitution even in the presence of strong electron‐donating groups and enables de‐tert‐butylation required for the complete annulation. Also demonstrated is the applicability of the method to introduce five‐, six‐, and seven‐membered rings containing oxygen, whereas multiple annulations also open up a short synthetic path to ladder‐type O‐heteroacenes and oligodibenzofurans. [ABSTRACT FROM AUTHOR]

Strongly dissymmetric circularly polarised (CP) luminescence from small organic molecules could transform a range of technologies, such as display devices. However, highly dissymmetric emission is usually not possible with small organic molecules, which typically give dissymmetric factors of photoluminescence (gPL) less than 10−2. Here we describe an almost 103‐fold chiroptical amplification of a π‐extended superhelicene when embedded in an achiral conjugated polymer matrix. This combination increases the |gPL| of the superhelicene from approximately 3×10−4 in solution to 0.15 in a blend film in the solid‐state. We propose that the amplification arises not simply through a chiral environment effect, but instead due to electrodynamic coupling between the electric and magnetic transition dipoles of the polymer donor and superhelicene acceptor, and subsequent CP Förster resonance energy transfer. We show that this amplification effect holds across several achiral polymer hosts and thus represents a simple and versatile approach to enhance the g‐factors of small organic molecules. [ABSTRACT FROM AUTHOR]

Alumina‐mediated CF activation (AmCFA) is an established method to generate incipient phenyl cation (IPC) through polarization of C(aryl)F bonds. Herein, it is reported that AmCFA can be used to induce intramolecular arylation of aryl alkynes containing one, two, and three triple bonds. During the reaction, a single formally eliminated hydrogen fluoride (HF) leads to the formation of two, three, and four CC bonds, respectively. Thus, the transformation gives rapid access to π‐extension and serves as an interesting example of solid‐state rational domino annulation enabling the bottom‐up construction of nanographenes. [ABSTRACT FROM AUTHOR]

Two‐dimensional acenes are promising candidates for applications in single‐molecule spectroscopy due to the electronic properties caused by their zig‐zag periphery. However, synthetic access to their dimers remains unexplored because of low solubility and reduced stability. Herein we report a facile approach towards two‐dimensional acenes dimers on the example of 2.3,8.9‐dibenzanthanthrene (DBATT) connected via rigid linker. The exploitation of dehydrative π‐extension on the last step of the synthesis allows avoiding difficulties connected with cumbersome purification of low soluble products. The technique was shown to be applicable for the synthesis of DBATT dimers connected rigidly with conjugated and non‐conjugated linkers, containing alternating para‐phenylene and bicyclo[2.2.2]octane moieties. [ABSTRACT FROM AUTHOR]

Large polycyclic aromatic hydrocarbons (PAHs) containing pentagons represent an important class of compounds that are considered to be superior materials in future nano‐electronic applications. From this perspective, the development of synthetic approaches to large PAHs and nanographenes (NGs) is a matter of great importance. In this context indenoannulation appears to be the most practical way to introduce pentagons into NGs. Here we report that alumina‐mediated C−F bond activation is an attractive tool for the synthesis of non‐alternant NGs bearing several pentagons. The unique nature of the reaction leads to a rather counter‐intuitive outcome and allows considering each previous aryl–aryl coupling as a promoter of the following one, despite the continuous increase in the strain energy. Thus, the presented strategy combines both facile synthesis and significant yields for large nonalternant PAHs and NGs. [ABSTRACT FROM AUTHOR]

The unique nature of the alumina‐mediated cyclodehydrofluorination gives the opportunity to execute the preprogrammed algorithm of the C−C couplings rationally built into a precursor. Such multi‐assemblies facilitate the construction of the carbon‐skeleton, superseding the conventional step‐by‐step by the one‐pot intramolecular assembly. In this work, the feasibility of the alumina‐mediated C−F bond activation approach for multi‐assembly is demonstrated on the example of a fundamental bowl‐shaped polycyclic aromatic hydrocarbon (diindenochrysene) through the formation of all "missing" C−C bonds at the last step. Beside valuable insights into the reaction mechanism and the design of the precursors, a facile pathway enabling the two‐step synthesis of diindenochrysene was elaborated, in which five C−C bonds form in a single synthetic step. It is shown that the relative positions of fluorine atoms play a crucial role in the outcome of the assembly and that governing the substituent positions enables the design of effective precursor molecules "programmed" for the consecutive C−C bond formations. In general, these findings push the state of the field towards the facile synthesis of sophisticated bowl‐shaped carbon‐based nanostructures through multi‐assembly of fluoroarenes. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of a novel buckybowl catcher that has a high affinity for C70 fullerene molecules. The catcher, made by cross-coupling two bowl-shaped bromoindacenopicene moieties with a tolyl linker, demonstrates the potential for creating sensors for spherical aromaticity. The researchers describe the catcher as a "miraculous, marvelous Fabergé artwork" that carefully frames the C70 fullerene. The full research article provides more information on this topic. [Extracted from the article]

By exposure of α‐fluorinated benzophenones to McMurry reaction conditions, we have observed the remarkable formation of 9,10‐diphenylanthracene derivatives. This unexpected transformation necessitates the cleavage of the exceptionally stable aromatic C−F bond under mild McMurry conditions. In this work, the condensation of several related fluorinated benzo‐ and acetophenones has been investigated, which allow us to propose a domino‐like fusion mechanism for this unusual transformation. The scope and limitations of the fluorine‐promoted benzophenone fusion are subsequently discussed. C−C coupling: It has been found that α‐fluorinated benzophenones undergo unusual fusion under standard McMurry conditions (see figure) leading to the formation anthracene derivatives that necessitate the cleavage of the exceptionally stable aromatic C−F bond. The discovered reaction proves that fluoroorganic chemistry still remains an undeveloped and extremely promising field. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis and characterization of a new type of a highly conjugated heterocyclic π‐chromophore, consisting of a central triphenylene core fused with three perylene monoimide units (star‐shaped molecules), is described. By judicious bay functionalization with tert‐butylphenoxy substituents, aggregation was completely prevented by using 1,1,2,2‐tetrachloroethane, allowing for a straightforward purification and, for the very first time, the complete separation of the constitutional isomers by HPLC. Both isomers can be easily distinguished by means of several conventional spectroscopic techniques. Furthermore, we have illustrated the absence of supramolecular aggregates and enhanced processability by noncovalent functionalization of graphene substrates, showing an outstanding homogeneity and demonstrating a different doping behavior in both isomers, making it possible to distinguish them by Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Die intramolekulare Aryl ‐ Aryl ‐ Kupplung ist die Schlüsselumwandlung in der rationalen Synthese von Nanographenen und Nanobändern. In dieser Hinsicht erwies sich die C ‐ F ‐ Bindungsaktivierung als eine vielseitige Alternative, die die Synthese mehrerer einzigartiger Kohlenstoff ‐ basierter Nanostrukturen ermöglicht. Hier beschreiben wir eine beispiellos anspruchsvolle Transformation, die zeigt, dass die C ‐ F ‐ Bindungsaktivierung durch Aluminiumoxid eine hochwirksame Domino ‐ C ‐ C ‐ Bindungsbildung ermöglicht. Trotz der flexiblen Struktur der Oligophenylen ‐ basierten Vorstufen gelingt ein effizienter regioselektiver Aufbau der Zielstrukturen. Die Fluorpositionen in der Vorstufe geben eindeutig das “Reißverschluss ‐ Programm” vor, welches zu einem Aufrollen von linearen Oligophenylenketten um einen Phenylrest führt und die gewünschten Nanographene ergibt. Das hoch effiziente Verfahren ist attraktiv für die Synthese nichtsubstituierter Nanographenen, die durch alternative Methoden in reiner Form schwer zugänglich sind. Eine anspruchsvolle Transformation besteht in der programmierten Umwandlung von nahezu linearen fluorierten Oligophenylenen zu Nanographenen durch effektive Domino ‐ Aryl ‐ Aryl ‐ Kupplung. Fluorsubstituenten in der Vorstufe geben die Bahn des „H ‐ F ‐ Reißverschlusses” eindeutig vor, der zur Bildung einer Nanographen ‐ Zielstruktur führt. [ABSTRACT FROM AUTHOR]

Intramolecular aryl-aryl coupling is the key transformation in the rational synthesis of nanographenes and nanoribbons. In this respect the C−F bond activation was shown to be a versatile alternative enabling the synthesis of several unique carbon-based nanostructures. Herein we describe an unprecedentedly challenging transformation showing that the C−F bond activation by aluminum oxide allows highly effective domino-like C−C bond formation. Despite the flexible nature of oligophenylene-based precursors efficient regioselective zipping to the target nanostructures was achieved. We show that fluorine positions in the precursor structure unambiguously dictate the 'running of the zipping-program' which results in rolling-up of linear oligophenylene chains around phenyl moieties yielding target nanographenes. The high efficiency of zipping makes this approach attractive for the synthesis of unsubstituted nanographenes which are difficult to obtain in pure form by other methods. [ABSTRACT FROM AUTHOR]

In this report the successful generation of the non-isolated pentagon rule (non-IPR) fullerene fragment via regioselective cyclodehydrofluorination of a specially designed precursor under laser ionization condition is presented. It is demonstrated that the transformation of the precursor molecule to the highly strained non-IPR bowl-shaped hydrocarbon can be achieved effectively at rather low laser fluences, despite the presence of fused pentagons in the structure. This finding opens up a venue towards the rational synthesis of individual isomers of non-IPR fullerenes and other related non-IPR architectures by the bottom-up strategy. The retrosynthetic analysis of fluoroarene-based precursor molecules for non-IPR fullerenes C36-C50 is discussed. [ABSTRACT FROM AUTHOR]

Hexa- peri-hexabenzocoronides (HBC) was successfully used as a model system for investigating the complex mechanism of the reductive functionalization of graphene. The well-defined molecular HBC system enabled deeper insights into the mechanism of the alkylation of reductively activated nanographenes. The separation and complete characterization of alkylation products clearly demonstrate that nanographene functionalization proceeds with exceptionally high regio- and stereoselectivities on the HBC scaffold. Experimental and theoretical studies lead to the conclusion that the intact basal graphene plane is chemically inert and addend binding can only take place at either preexisting defects or close to the periphery. [ABSTRACT FROM AUTHOR]

We report on the synthesis and the structure elucidation of the elusive azafullerene pentachloride C59NCl5, which was obtained by high temperature halogenation of (C59N)2. The exceptionally strong host-guest interaction of the title compound in the solid is discussed. [ABSTRACT FROM AUTHOR]

We report on the synthesis and the structure elucidation of the elusive azafullerene pentachloride C59NCl5, which was obtained by high temperature halogenation of (C59N)2. The exceptionally strong host-guest interaction of the title compound in the solid is discussed. [ABSTRACT FROM AUTHOR]

Halogenated buckybowls or bowl-shaped polycyclic aromatic hydrocarbons (BS-PAHs) are key building blocks for the 'bottom-up' synthesis of various carbon-based nanomaterials with outstanding potential in different fields of technology. The current state of the art provides quite a limited number of synthetic pathways to BS-PAHs; moreover, none of these approaches show high selectivity and tolerance of functional groups. Herein we demonstrate an effective route to BS-PAHs that includes directed intramolecular aryl-aryl coupling through C−F bond activation. The coupling conditions were found to be completely tolerant toward aromatic C−Br and C−Cl bonds, thus allowing the facile synthesis of rationally halogenated buckybowls with an unprecedented level of selectivity. This finding opens the way to functionalized BS-PAH systems that cannot be obtained by alternative methods. [ABSTRACT FROM AUTHOR]

We report on thermal C-F bond activation in fluoroarenes by various metal oxides leading to effective C-C bond formation via cyclodehydrofluorination. We demonstrate that the transformation of the precursor molecule to the respective model nanographene/nanoribbon can be realized rather effectively on various metal oxides. It is found that intramolecular Aryl-Aryl cyclization via cyclodehydrofluorination can be performed at relatively mild condition. Our finding opens up a venue toward rational synthesis of carbon-based nanomaterial by bottom-up strategy directly on insulating metal oxide surfaces. [ABSTRACT FROM AUTHOR]

We report a theoretical approach for synthesis of precursors for the rational synthesis of chirality-pure single-walled carbon nanotubes (SWCNT) by surface-assisted method. The presented combinatorial strategy in combination with the mass-selective deposition technique provides a simple access to precursors for SWCNT of various chiralities, including large diameter tubes. The synthetic strategy provides a simple access to the robust SWCNT precursors 'preprogrammed' for 54 different chiralities, starting from just four simple cyclic ketones. The molecules exhibit a rigid and fully fused structure which is expected to be important for a highly efficient conversion to ultra-short SWCNTs and for high yield of the respective isomer-pure tubes. The advantages and limitations of the approach for the preparative production of chirality pure SWCNTs are discussed. [ABSTRACT FROM AUTHOR]

We report an effective strategy for preparing robust precursors for the rational synthesis of helicity-pure single-walled carbon nanotubes (SWCNTs) by a surface-assisted strategy. The approach presented allows simple access to large-diameter SWCNT precursors. The efficiency of the strategy is demonstrated by the synthesis of four robust precursors for the preparation of (6,6), (8,8), (10,10), and (12,12) armchair SWCNTs. The molecules exhibit a rigid and fully fused structure, which is expected to be important for a highly efficient conversion to CNT seeds and a high yield of the respective helicity-pure SWCNTs. The presented synthetic approach provides simple access to robust SWCNT precursors that can be 'programmed' for virtually any helicity. [ABSTRACT FROM AUTHOR]

Keywords: alkyne activation; alumina; buckybowls; C-F activation; geodesic nanoribbons EN alkyne activation alumina buckybowls C-F activation geodesic nanoribbons 1 1 1 06/06/22 20220601 NES 220601 B Tandem bond activation b : The dual Lewis acidity of alumina has been discovered and employed to activate C-F and triple C C bonds in a tandem manner to provide rapid access to elusive nonplanar PAHs such as -extended helicenes, buckybowls and fragments of geodesic nanoribbons. Alkyne activation, alumina, buckybowls, C-F activation, geodesic nanoribbons. [Extracted from the article]

Wrap up: A specially fluorinated C60 fullerene precursor (see figure) was converted to the target C60 cage by laser ionization, resulting in highly selective HF elimination without any detectable side reactions or undesired fragmentation. The fully selective transformation to the target fullerene has been unambiguously demonstrated from a 13C‐labeled precursor. In general the findings open new horizons for the synthesis of carbon‐based nanomaterials, which cannot be obtained by any conventional alternative method. [ABSTRACT FROM AUTHOR]

Spin and charge transport: The electronic and structural properties obtained from KC60(THF)5⋅2 THF single crystals are reported (see picture). An important finding is the presence of one‐dimensional electric conductivity and the observation of counterintuitive anisotropy for electron transport. [ABSTRACT FROM AUTHOR]

We report herein the synthesis of six precursor molecules for the rational synthesis of isomerically pure armchair, zigzag, or chiral single-walled carbon nanotubes (SWCNTs). The polycyclic aromatic hydrocarbons possess the required carbon connectivity for the generation of extended hemispherical buckybowls with predefined geometry through intramolecular cyclodehydrogenation. The precursors for the short carbon nanotubes and the large-diameter hemispherical buckybowls have potential for the rational initiation of single-chirality SWCNT growth on metal surfaces. The options for the construction of precursors for various SWCNT chiralities based on the suggested synthesis strategy are presented. [ABSTRACT FROM AUTHOR]

Although all fullerenes do not satisfy the classical aromaticity condition, as a result of their nonplanar nature, they experience effective stabilization due to extensive cyclic π-electron delocalization and exhibit pronounced 'spherical aromaticity'. This feature has raised the question of the opposite phenomenon, that is, the existence of antiaromatic carbon cages. Here the first experimental evidence of the existence of antiaromatic fullerenes is reported. The elusive #6094C68 was effectively captured as C68Cl8 by in situ chlorination in the gas phase during radio-frequency synthesis. The chlorinated cage was separated by means of multistage HPLC, and its connectivity unambiguously determined by single-crystal X-ray analysis. Halogen-stripped pristine #6094C68 was monitored by mass spectrometry of the chlorinated C68Cl8 cage. Quantum chemical calculations reveal the highly antiaromatic character of #6094C68, in accordance with all geometric, energetic, and magnetic criteria of aromaticity. Chlorine addition leads to substantial stabilization of the cage owing to aromatization in the resulting C68Cl8, which explains its high abundance in the primary fullerene soot. This work provides new insights into the process of fullerene formation and better understanding of aromaticity phenomena in general. [ABSTRACT FROM AUTHOR]

Front Cover: Domino Dehydrative -Extension: A Facile Path to Extended Perylenes and Terrylenes (Chem. Eur. J. 69/2021) Keywords: domino reactions; perylenes; pi-extension; polycyclic aromatic compounds; terrylenes EN domino reactions perylenes pi-extension polycyclic aromatic compounds terrylenes 17264 17264 1 12/13/21 20211209 NES 211209 B Selective activation of identical functional groups b is one of the most challenging tasks in the realm of organic chemistry. Domino reactions, perylenes, pi-extension, polycyclic aromatic compounds, terrylenes. [Extracted from the article]

Carbon origami, C-F bond activation, multihelical nanographenes, aryl-aryl coupling, cyclodehydrofluorination Cover Feature: Carbon Origami via an Alumina-Assisted Cyclodehydrofluorination Strategy (Chem. Eur. J. 20/2021) Keywords: aryl-aryl coupling; carbon origami; C-F bond activation; cyclodehydrofluorination; multihelical nanographenes EN aryl-aryl coupling carbon origami C-F bond activation cyclodehydrofluorination multihelical nanographenes 6103 6103 1 04/09/21 20210407 NES 210407 B Rational folding of nanographenes b has the potential to penetrate the barrier between macro- and micro-worlds for the engineering of carbon-based materials with functional molecular shapes. [Extracted from the article]

Corrigendum: Bottom-Up C60 Fullerene Construction from a Fluorinated C60H21F9 Precursor by Laser-Induced Tandem Cyclization In the published paper, a frontispiece graphic was included that has subsequently been deemed incompatible with Chemistry Europe's commitment to champion integrity and diversity. [Extracted from the article]

Despite conventional opinion on high inertness of aluminum oxide and exceptional stability of the carbon–fluorine bond, activated γ‐alumina effectively polarizes the C–F bond. This process is known to implement effective C–C coupling in the cove region, leading to intramolecular annulation and formation of non‐alternant polycyclic aromatic hydrocarbons (PAHs). Herein, the importance of the cove region geometry on annulation efficiency is shown. This is demonstrated using precursor 1 as a model, which allows investigation of the cove region's major feature, namely its helical geometry, and effect of its structure on the efficiency of intramolecular C–C bond formation. Herein, the synthesis of 1, its behavior on activated alumina, and reasoning for the observed outcomes are described. [ABSTRACT FROM AUTHOR]

A combination of low energy ion beam deposition and mass resolved thermal desorption spectroscopy is applied to analyze the binding behavior of two nonplanar polycyclic aromatic hydrocarbons (PAHs) to highly oriented pyrolytic graphite (HOPG) surfaces—also concerning their lateral dispersion interactions. In particular, the fullerene precursor C60H30 (FPC) and rubrene C42H28 are studied. Due to their smaller contact areas, both molecules exhibit significantly weaker binding energies to the HOPG surface compared to planar PAHs of similar size: C60H30 is bound to the surface by 3.04 eV, which is 0.6 eV lower than for a fully planar homologue. For rubrene, an isolated molecule–substrate binding energy of 1.59 eV is found, which is about 1 eV less than that of the corresponding planar homologue hexabenzocoronene C42H18. In contrast to FPC, rubrene shows a significant (intermolecular) lateral dispersion contribution to the binding energy as the submonolayer coverage increases. [ABSTRACT FROM AUTHOR]

In contrast to the vast majority of reactions dealing with strain energies inherent to synthesis of non-alternant PAHs, alumina-mediated C-F bond activation turns out to be more sensitive to electronic effects rather than steric. In contrast to the vast majority of reactions dealing with strain energies inherent to synthesis of non-alternant PAHs, alumina-mediated C-F bond activation turns out to be more sensitive to electronic effects rather than steric. Aromatization, buckybowls, C-C coupling, C-F activation, indenoannulation. [Extracted from the article]