Kinetically stabilized 1,3-diarylisobenzofurans and the possibility of preparing large, persistent isoacenofurans with unusually small HOMO–LUMO gaps

• Qian Liu and
• Glen P. Miller

Beilstein J. Org. Chem. 2024, 20, 1099–1110, doi:10.3762/bjoc.20.97

• gaps is achievable. As such, these molecules deserve increased attention as potential p-type organic semiconductors. Keywords: acene; DFT calculation; highly delocalized π-system; isoacenofuran; isobenzofuran; kinetically stabilized; organic semiconductor; small HOMO–LUMO gap; synthesis; Introduction

• aromatic sextet in any neutral, closed-shell resonance form (Figure 2). Thus, compared to the corresponding acene, an isoacenofuran could possess a more highly delocalized π-system and an even smaller HOMO–LUMO gap. For example, consider pentacene and isotetracenofuran. Pentacene can be drawn in several

• the furan ring possesses an aromatic sextet (Figure 2). The remaining π-electrons of isotetracenofuran are fully delocalized over the remaining four rings. This analysis suggests that all isoacenofurans should possess a more highly delocalized π-system than their acene counterparts, and potentially