Oxygen‐Doped Zig‐Zag Molecular Ribbons

Abstract

The synthesis of azig-zag oxygen-doped molecular rhombic ribbon has been achieved.T his includes oxidative C À Ca nd C À Ob ond formations that allowed the stepwise elongation and planarization of an oxa-congener of 2,7periacenoacene.X -rayd iffraction analysis corroborated the flat structure and the zig-zag topology of the O-doped edges. Photophysical and electrochemical investigations showed that the extension of the peri-xanthenoxanthene (PXX) into the molecular ribbon induces an oticeable shrinking of the molecular band gap devised by ar ising of the HOMO energy level, ad esirable property for p-type organic semiconductors.

Combining high-resolution scanning tunnelling microscopy and first-principles simulations to identify halogen bonding

“…3,9-Br 2 PXX (Fig. 1a) is a dibrominated derivative of PXX, an electron donor molecule [50][51][52][53] , derivatives of which have previously been employed as p-type semiconductors in organic thin-film transistors due to their efficient carrier injection properties, high mobility, and thermal stability 54,55 . The Br and O atoms in 3,9-Br 2 PXX offer the possibility of both HB and XB intermolecular interactions when arranged into supramolecular arrays on a surface.…”

Open-Shell Graphene Fragments

“…131 Interestingly, it is found that from the hexarylene onward, a weak shoulder at the lowestenergy edge of the absorption spectra was peri-acenoacenes (Figure 9A). 132 Different from the rectangular peri-acenes, [n,m]periacenoacenes possess two pairs of parallelly aligned zigzag edges. The existence of four zigzag edges may also lead to the appearance of an open-shell character.…”

Tailored Synthesis of N-Substituted peri-Xanthenoxanthene Diimide (PXXDI) and Monoimide (PXXMI) Scaffolds

“…Our studies commenced by examining the homocoupling method using CuO in refluxing PhNO 2 , which gave 1 Oct in 13% yield. When using CuI and PivOH in DMSO at 150 °C for 5 h in air, [5][6][7]10 we improved the yield to 20%. Simultaneously to our investigations, a related work by Kamei et al describing the high-yielding synthesis of A 2 -type PXXDIs following the IP strategy using CuCl in DMSO at 120 °C appeared as a patent.…”

“…3 The re-emergence of such interesting PXX-based chromophores recently engendered synthetic programs in our and other laboratories. 4 Our group has expanded the structural diversity of PXX and developed a variant of the oxidative Pummerer O-annulation reaction to prepare perisubstituted PXXs featuring ribbon-like structures with either armchair 5 or zig-zag 6 peripheries and π-extended surfaces. 7 Very recently, we prepared the first mimics of naphthalene-diimide (NDI), 8 perylene-monoimide (PMI) and -diimide (PDI) molecules, 9 in which the PXX core exposes either one (PXXMI) or two (PXXDI) alkylimide groups (Figure 1).…”