Challenges in the synthesis of corannulene-based non-planar nanographenes on Au(111) surfaces

Solid State Self-Assembly of an Extended Curved-Arm Nickel(II) Macrocycle with Fullerene C60

Three new co-crystalline structures are reported that contain fullerene C60 with the under-represented Ni(II)-dibenzotetraaza[14]annulene derivative, (5,14-dihydro-6,8,15,17-tetrabenzyl-2,3,11,12-tetramethyldibenzo[b,i][1,4,8,11]tetraazacyclo-tetradecine)nickel(II), [Ni(Bz4TMTAA)]. The single-crystal X-ray analysis shows that the three studied compounds crystallize in the monoclinic C2/c, Pnma orthorhombic and triclinic P1 , c h a r / 0 x 00 A F n o t i m p l e m e n t e d ${1,char/0x00AF not implemented}$ space groups, with the two former compounds being polymorphs that are isostructural but differ in their symmetries. From the crystallographic results, a common packing arrangement is established, with C60 and [Ni(Bz4TMTAA)] molecules organised around one-dimensional hollow channels, associated 1 : 1 and 1 : 2 complexation of the macrocycle and the fullerene molecules, the latter being organised into hexagonal arrays. Interestingly, one of the structures showed a skewed hexagonal channel arrangement with the introduction of water molecules. Hirshfeld surface analyses have been used to investigate non-covalent interactions and cumulative π…π, C-H…π, H…H, and N…C60 interactions between fullerene C60 and [Ni(Bz4TMTAA)] host molecule which are deemed the stabilizing factors for forming the sophisticated arrangements in the solid-state. differences.

Synthesis and Characterization of a Non-Planar Cyclophenylene on Au(111)

We report the surface-assisted synthesis of a non-planar cyclophenylene derivative containing four meta- and two para- connected phenylene moieties on Au(111), via hierarchical Ullmann coupling of a 1,10-dibrominated angular [3] phenylene and subsequent C-C bond cleavage at the four-membered rings. Scanning tunneling microscopy and spectroscopy (STM/STS) were used for the characterization of its chemical structure and electronic properties. Density functional theory (DFT) calculations support the experimental observations.

Chemisorption-Induced Formation of Biphenylene Dimer on Ag(111)

We report an example that demonstrates the clear interdependence between surface-supported reactions and molecular-adsorption configurations. Two biphenyl-based molecules with two and four bromine substituents, i.e., 2,2'-dibromobiphenyl (DBBP) and 2,2',6,6'-tetrabromo-1,1'-biphenyl (TBBP), show completely different reaction pathways on a Ag(111) surface, leading to the selective formation of dibenzo[e,l]pyrene and biphenylene dimer, respectively. By combining low-temperature scanning tunneling microscopy, synchrotron radiation photoemission spectroscopy, and density functional theory calculations, we unravel the underlying reaction mechanism. After debromination, a biradical biphenyl can be stabilized by surface Ag adatoms, while a four-radical biphenyl undergoes spontaneous intramolecular annulation due to its extreme instability on Ag(111). Such different chemisorption-induced precursor states between DBBP and TBBP consequently lead to different reaction pathways after further annealing. In addition, using bond-resolving scanning tunneling microscopy and scanning tunneling spectroscopy, we determine with atomic precision the bond-length alternation of the biphenylene dimer product, which contains 4-, 6-, and 8-membered rings. The 4-membered ring units turn out to be radialene structures.

Graphitic supramolecular architectures based on corannulene, fullerene, and beyond

In this Feature Article, we survey the advances made in the field of fulleretic materials over the last five years. Merging the intriguing characteristics of fulleretic molecules with hierarchical materials can lead to enhanced properties of the latter for applications in optoelectronic, biomaterial, and heterogeneous catalysis sectors. As there has been significant growth in the development of fullerene- and corannulene-containing materials, this article will focus on studies performed during the last five years exclusively, and highlight the recent trends in designing fulleretic compounds and understanding their properties, that has enriched the repertoire of carbon-rich functional materials.