19399-64-5Relevant academic research and scientific papers
Revisiting Kekulene: Synthesis and Single-Molecule Imaging
Pozo, Iago,Majzik, Zsolt,Pavli?ek, Niko,Melle-Franco, Manuel,Guitián, Enrique,Pe?a, Diego,Gross, Leo,Pérez, Dolores
supporting information, p. 15488 - 15493 (2019/10/16)
Four decades after the first (and only) reported synthesis of kekulene, this emblematic cycloarene has been obtained again through an improved route involving the construction of a key synthetic intermediate, 5,6,8,9-tetrahydrobenzo[m]tetraphene, by means of a double Diels-Alder reaction between styrene and a versatile benzodiyne synthon. Ultra-high-resolution AFM imaging of single molecules of kekulene and computational calculations provide additional support for a molecular structure with a significant degree of bond localization in accordance with the resonance structure predicted by the Clar model.
Cycloarenes, a New Class of Aromatic Compounds, I. Synthesis of Kekulene
Staab, Heinz A.,Diederich, Francois
, p. 3487 - 3503 (2007/10/02)
Definition and nomenclature of cycloarenes, a new class of aromatic compounds, are discussed.Cyclododecakisbenzene ("kekulene", 1) has been synthesized as the first representative of cycloarenes. - From the dithiaphane 11 by double sulfur extrusion, either photochemically or by pyrolysis of disulfone 12, the carbocyclic system 13 was formed which by dehydrogenation yielded 14.By Stevens rearrangement of 11 followed by elimination the phanediene 15 was obtained which was dehydrogenated to 18.From 15 by photo-cyclodehydrogenation in excellent yield the octahydrokekulene 19 was obtained.The different reactivity of 15 and 18 in the photo-cyclodehydrogenation is discussed in terms of electronic and steric effects.Dehydrogenation of 19 yielded 1.
