Pyrenes, Peropyrenes, and Teropyrenes: Synthesis, Structures, and Photophysical Properties

Abstract

The design of ar elatively simple and efficient method to extend the p-conjugation of readily available aromatics in one-dimension is of significant value.I nt his paper,pyrenes,peropyrenes,and teropyrenes were synthesized through ad ouble or quadruple benzannulation reaction of alkynes promoted by Brønsted acid. This novel method does not involve cyclodehydrogenation (oxidative aryl-aryl coupling) to arrive at the newly incorporated large arene moieties. All of the target compounds were synthesized in moderate to good yields and were fully characterized with the structures unambiguously confirmed by X-ray crystallography.A s expected, photophysical characterization clearly shows increasing red-shifts as af unction of extended conjugation within the fused ring systems.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under http://dx.Figure 3. Excitation (left) and emission( right) spectra of a) 3a (solid line; l exc = 353 nm and l em = 389 nm), b) 6b (dashed line; l exc = 465 nm and l em = 487 nm), and c) 10 a (dotted line; l exc = 570 nm and l em = 591 nm) in toluene at 298 K.

Facile Synthesis of Aryl-Substituted Cycloarenes via Bismuth(III) Triflate-Catalyzed Cyclization of Vinyl Ethers

“…A conceptual synthetic strategy toward cycloarenes is to build up initially, the macrocyclic oligo(m-phenylene) precursors carrying alkyne/alkene groups on the outer periphery, followed by Brønsted acid or Lewis acid-catalyzed cyclization reaction. [15][16][17][18][19][20][21] Our initial effort of using acid-catalyzed cyclization of alkyne precursors was not successful after many attempts. Fortunately, we found that the Bi(OTf) 3 -catalyzed cyclization reaction of vinyl ether developed by Murai et al 22 was efficient (Scheme 1).…”

Synthesis and Properties of Nitrogen-Containing Pyrenes

“…The triazapyrene skeleton in 3a contains planar structures. 10,11 The dihedral angles between the triazapyrene moiety and benzene rings are 51° and 59°. Triazapyrene 3a formed head-to-tail dimers with the distance of 3.40 Å between least-squares planes of the triazapyrene core.…”

Tetrasubstituted Peropyrenes Formed by Reductive Aromatization: Synthesis, Functionalization and Characterization

“…[28] A more convenient protocol was developed by Chalifoux and co-workers who built up the peropyrene scaffold by acid mediated intramolecular benzannulation of internal alkynes (Scheme 2a). [29][30][31] This approach enables the functionalization of the bay positions of peropyrene and leads therefore to twisted peropyrens with up to 18°out of plane twist angle and axial chirality. [30] The most twisted representative is a tetranaphthyl annulated peropyrene built up via oxidative Scholl dehydrogenation of a tetranaphthyl-diphenylbenzene precursor reported by the group of Miao (Scheme 2b) [32] and later extended with pyrene functionalities by Feng.…”