Themed collection Aromaticity

Showcasing a collection of cutting edge contributions by international leaders in the field of aromaticity.

Ligand-stabilized early main group metal hydride clusters.

Fusion of porphyrins with other aromatic units at the meso- and β-positions results in very strong bathochromic shifts of absorption.

Coarctate reactivity, typical of molecules in the conjugated ‘ene–ene–yne’ manifold, can be harnessed to generate unique classes of heterocyclic compounds.

This feature article overviews and summarizes aromaticity of the four-membered ring systems to discuss expanding chemistry of the aromaticity concept.

Aryl–aryl bonds can effectively be formed using molybdenum pentachloride to obtain uncommon geometries tolerating a broad scope of functional groups.

Triphenylamine-based fluorophores containing pyrene or corannulene show variable fluorescence quenching sensitivity toward nitro explosives.

Reduction of a 4,5,6-triphospha[3]radialene gave the corresponding isolable dianionic species.

A “V”-shaped Hammett plot shows that resonance-assisted hydrogen bonding does not dictate the strength of the intramolecular hydrogen bond in the E isomers of hydrazone-based switches.

We present a general scheme for estimation of aromatic stabilization energies of benzenoid hydrocarbons based on selected topological features.

The interaction between C₆₀ and tetrabenzoquadrannulene, observed by X-ray diffraction analysis, is understood using DFT-D calculations and a sphere-in-cone model.

Intramolecular cyclization of alkynyl-substituted derivatives of the Green Fluorescent Protein chromophore into benzofuran derivatives presents a simple way of enhancing its fluorescence.

The LOLIPOP criterion identifies π-depleted polyaromatic molecules, which exhibit enhanced π-stacking ability.

Iodine-catalyzed cyclization is used to prepare benzodifurans that can be further functionalized to alter their properties.

A bay-bridging Scholl reaction converts the pentaphenylphenyl-substituted tribenzotriquinacene 1 into the curved hexa-peri-hexabenzocoronene-TBTQ derivative 2 bearing a newly formed cycloheptatriene ring.

A series of quadrupolar bis(p-aminophenyl)-carbo-benzenes (bottom) is compared to the acyclic carbo-butadiene (top) reference series.

We report a two-photon probe (FS1) which shows a 21-fold two-photon excited fluorescence enhancement in response to H₂S and can selectively detect H₂S in a rat hippocampal slice at a depth of 90–190 μm by using two-photon microscopy.

The high energy of cyclobutadiene (CBD) is not due primarily to “anti-aromaticity,” but rather to angle strain and Pauli repulsion between close-by parallel CC σ and π bonds.

The mesomorphic properties of a series of novel dibenz[a,c]anthracenes display remarkable sensitivity to substituents and in some cases these compounds exhibit mesophases over broad temperature ranges.

Annulation of thiophenes directly into the bay regions of rylene dyes leads to core-extended rylene tetracarboxylic diimides with interesting electro-optical properties.

We report the synthesis and charge transport characterization of soluble hexacenes, including ambipolar behavior from an octafluoro hexacene.

The relative aromaticity of COT²⁻ is experimentally as large as benzene, and larger than that of the cyclopentadienide anion.

The palladium-catalysed heteroannulation of [60]fullerene with N-benzyl sulfonamides via C–H activation affords [60]fullerene-fused tetrahydroisoquinolines, which can be further functionalised.

A series of hexa-peri-hexabenzocoronenes with electron withdrawing groups were obtained via oxidative cyclodehydrogenation with an oxidant and a strong acid.

Acetylene might suffice as a dienophile for growing uniform carbon nanotubes from small hydrocarbon templates by the Diels–Alder cycloaddition/rearomatization strategy.

O₂ plasma treated GO with a work function of 5.2 eV as a high performance hole transport layer in organic solar cells.

Antiaromaticity of fluorenyl cations can be moderated through the use of substituents to change the amount of charge density.

1,4,5,8-Tetraethynylnaphthalene derivatives were synthesized for the first time. X-ray crystallographic structure analysis of the tetrakis(phenylethynyl) substituted derivative revealed three different modes of distortion to reduce steric repulsion.

Tetrakis(4-tert-butylphenyl) substituted and fused quinoidal porphyrins are prepared for the first time, which show unique geometry, electronic structure and optical properties.

A multicomponent reaction and a double McMurry/valence isomerization/dehydrogenation reaction conspire to create the entire pyrene system in a highly decorated [12](1,6)pyrenophane.

A semi-one-pot synthesis of phenanthrenes from styrenes and arenes has been developed which provides an effective and practical protocol.

A functionalised cyclobis(paraquat-p-phenylene) attached by a rigid linker to a tetrathiafulvalene unit, which is incapable of self-complexation, forms preferentially a [c2]daisy chain which undergoes rapid disassociation and reassociation on the ¹H NMR time-scale above room temperature.

Raman spectroscopic analysis of long α-oligofurans and polyfuran shows that extension of the π-conjugation in polyfuran spreads over 14–15 furan units.

We herein report a base-promoted generation and complexation of sterically hindered 1,3,5-triaryl 2-pyridylidene from the corresponding pyridinium salt.

New, curved boron-containing acenes have been synthesized, demonstrating cathodic electrochemistry, strong photoluminescence, and facile cross-coupling to give π-extended scaffolds.

A bisporphyrin macrocycle with an adaptable cavity showing a high binding selectivity for C₈₄ over lower fullerenes (C₆₀ and C₇₀).

The chalcogen atoms make a marked difference in the ground state electronic structure.

A prominent covalent bonding interaction between molecules is experimentally elucidated in a one-dimensional stack of an anthracene-linked bisphenalenyl Kekulé molecule by using polarized reflection spectroscopy.

Two fluorescent, diaza-analogues of tetracene can be prepared independently from a common triazene-ene-yne precursor via either a pericyclic or coarctate ring-forming reaction.

Treatment of 9-chloro-9-borafluorene with N,O-(bistrimethylsilyl)hydroxylamine produces an azaborine derivative.

Addition of SIMEF-O₂ to the active layer of organic photovoltaic devices decreased their performance.

A TTFV-phenylacetylene folding polymer exhibits the property of reversibly dispersing and releasing single-walled carbon nanotubes in organic solvents under the control of redox or pH stimuli.

Solvothermal dehydration of 1,1′-ferrocenediboronic acid produces single crystals of a triply ferrocene-bridged boroxine cyclophane.

Systematic investigations on Friedel–Crafts reactions from building blocks A, B and C have been carried out to demonstrate that the formation of pillar[5]arenes occurs under thermodynamic control.

Open-cage derivative C₆₀(O)₄(OH)₂(NC₆H₄^tBu)₂ reacts with ICl to form a Baeyer–Villiger type product, which yields an intense green product upon treatment with HI.