Synthesis of Pyrenes by Twofold Hydroarylation of 2,6-Dialkynylbiphenyls

Abstract

Cationic gold(I) complexes having Buchwald-type biarylphosphines effectively catalyzed twofold hydroarylation of 2,6-dialkynylbiphenyls to construct pyrene skeletons.

Construction of Polycyclic π‐Conjugated Systems Incorporating an Azulene Unit Following the Oxidation of 1,8‐Diphenyl‐9,10‐bis(phenylethynyl)phenanthrene

“…[36] The approximate arrangement of the aromatic and arylethynylg roups in 1 could be ap otential motif that could be used to construct ah ighly fused polycyclic system via alkyne benzannulation reactions. [37] Alkyne benzannulationr eactions using av ariety of Lewis/Brønsted acids [38][39][40][41][42][43][44][45] and some electrophiles [46,47] have been powerful strategies for the direct p-extensiono fa romatic compounds. [48][49][50] During the course of our study of phenanthrenes 1,w ef ound that the transannulation of 1a upon two-electron oxidation selectively afforded the azulene-embeddedP AH 2a,w hich exhibited long-wavelength absorption and amphoteric redox events originating from the non-alternant characteristics of the embedded azulene core.…”

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

“…Alkyne benzannulation reactions have been shown to proceed using av ariety of p-Lewis acids such as gold(III), [9] platinum(II), [10] ruthenium(II), [10b,c] indium(III), [10b,11] and antimony(V). [14] However,n either peropyrenes nor teropyrenes have been prepared through alkyne benzannulation reactions. [13] 4,10-Disubstituted pyrenes were successfully synthesized through ag old(I)-or platinum(II)catalyzed twofold benzannulation reaction of 2,6-dialkynylbiphenyls.…”

“…[13] 4,10-Disubstituted pyrenes were successfully synthesized through ag old(I)-or platinum(II)catalyzed twofold benzannulation reaction of 2,6-dialkynylbiphenyls. [14] However,n either peropyrenes nor teropyrenes have been prepared through alkyne benzannulation reactions. Herein, we report an efficient approach to generate soluble pyrene,p eropyrene,a nd teropyrene derivatives by ad ouble or quadruple benzannulation reaction of alkynes promoted by aB r ønsted acid.…”

Azulenophenanthrenes from 2,2′‐Di(arylethynyl)biphenyls through CC Bond Cleavage of a Benzene Ring

“…[2] We applied their hydroarylation reaction to the synthesis of pyrenes (Scheme 1); 4,10-disubstituted pyrenes were successfully synthesized by the gold-catalyzed twofold hydroarylation reaction of 2,6-dialkynylbiphenyls. [3] A phenyl ring having two alkynyl substituents at the 2 and 6 positions forms two vinylene bridges with a pendant phenyl ring, in parallel, to construct a pyrene skeleton. We envisaged that 2,2'-dialkynylbiphenyl would be an alternative starting material for another related intramolecular twofold hydroarylation.…”