Synthesis of acenes via coupling of 1,4-dilithiobutadienes with diiodoarenes in the presence of CuCl

9‐Stannafluorenes: 1,4‐Dimetal Equivalents for Aromatic Annulation by Double Cross‐Coupling

“…Considering that 1,4‐M 2 can be readily prepared from the corresponding 1,4‐X 2 and, in particular, the structural variation of available 1,2‐X 2 is much broader than that of 1,2‐M 2 : thus mode B‐type annulation could greatly expand the repertoire of accessible PAHs. However, the precedents of mode B‐type annulation were limited to only the reactions of 2,2′‐diborylbiphenyls,4a zirconacyclopentadienes,4b–d [Zr(2,2′‐biphenyldilyl) 3 ][Li⋅(THF) 4 ] 2 ,4e–g 2,2′‐distannylbinaphthyl,4h and 1,4‐dilithiobutadienes4j with 1,2‐dihalobenzenes, and there is still much room for improvement in the scope of the substrates and reagents, yields, and reaction conditions.…”

Strategies for the Synthesis of Higher Acenes

“…Thus, the cycloaddition of 45 with electron‐deficient alkynes or alkenes has been applied to the synthesis of functionalized dihydroacenes of type 46 , which can be converted either into the corresponding acenes 47 by dehydrogenation or into larger hydroacene derivatives through an iterative sequence (Scheme ) . Moreover, the iodination/lithiation of 45 gives rise to 1,4‐dilithiobutadienes 49 , which can be coupled with diiodoarenes in the presence of CuCl to afford dihydroacenes of type 50 …”

Three-Bond Breaking of Cyclic Anhydrides: Easy Access to Polyfunctionalized Naphthalenes and Phenanthrenes

“…Accordingly, the chemists continue to devise new synthetic methods to efficiently construct these structural motifs. Among various synthetic routes to π-conjugated naphthalenes, homologation of mono- or difunctionalized arenes have attracted much attention. Cyclotrimerization of arynes, benzannulation of biaryls, and cyclization of certain diarylethenes are developed synthetic strategies to phenanthrenes as well .…”