Corannulene: a molecular bowl of carbon with multifaceted properties and diverse applications

Abstract

Unlike typical polycyclic aromatic hydrocarbons, such as coronene, which are flat and planar, corannulene is a molecular bowl of carbon. It can be imagined as the cap region of fullerene C60 or an end of a single-walled carbon nanotube. This structural distinction manifests itself in unique properties. For example, corannulene exhibits bowl-flipping dynamics, electron accepting capability, and formation of a ball-in-socket type of interaction with C60. These varied properties allow for application of corannulene in a myriad of disciplines ranging from organic electronics and sensing to energy storage and self-assembly. In this feature article, our goal is to discuss the major synthetic developments in corannulene chemistry which allow the scientific community access to this beautiful molecule in a practical fashion, the unique properties of the corannulene nucleus that sets it apart from the planar polynuclear aromatic hydrocarbons, and lastly its applications in the arena of materials chemistry.

Corannulene‐Based Electron Acceptors: Combining Modular and Practical Synthesis with Electron Affinity and Solubility

“…Recently, there has been an impetus in the design and synthesis of non‐fullerene electron acceptors displaying high solubility, scalability, and ease of derivatization . Corannulene, with a recently developed kilogram‐scale synthesis, high solubility due to a lack of intermolecular π–π stacking interactions, and an adjustable structure is a suitable candidate for this purpose . Pristine corannulene, however, is not as good an electron acceptor as fullerene C 60 .…”

“…[1] Corannulene,w ith a recently developed kilogram-scale synthesis, [2] high solubility due to al ack of intermolecular p-p stacking interactions, and an adjustable structure is as uitable candidatef or this purpose. [3][4][5][6][7][8][9][10][11][12][13][14] Pristinec orannulene,h owever,i sn ot as good an electron acceptora sf ullerene C 60 .T herefore, scaffold modifications with electron-withdrawing groups have been identified as av iable route to enhancet he electron affinity of the aromatic nucleus. In this regard,B oltalina's fluorinated corannulene, [16] our bis-aryl sulfones, [27] and Lentz's bis-imides/cyano derivatives [32] produces an anodics hift of 1.23, 1.35, and 1.42 V, respectively,i nt he first reversible reductionp otential of corannulene.…”

Corannulenes with Electron‐Withdrawing Substituents: Synthetic Approaches and Resulting Structural and Electronic Properties

“…These studies have revealed the potential application of corannulene derivatives in molecular electronics, for example, as organic field‐effect transistors and as possible semiconductors . A feature article facing the very broad applications of corannulenes in materials science, including supramolecular chemistry, was recently published by Stuparu …”

“…[3] Af eature article facing the very broad applications of corannulenes in materials science, including supramolecular chemistry,w as recently published by Stuparu. [4] In the following review article, the focus will be on the synthesis and structural and electrochemical properties of corannulenes containing electron-withdrawing groups.…”

Bowl Inversion in an Exo‐type Supramolecule in the Solid State

“…[6] Theb owl-shaped geometry renders buckybowls as eries of unique properties,s uch as inherent dipole and asymmetrical assembly configuration. [7] These properties are reversed with bowl inversion. Fori nstance,t he direction of molecular dipole for buckybowl inverts with the bowl inversion, which is proposed to be potential in organic ferroelectric materials.…”