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Synthetic options for conversion of indeno[2,1‐c]fluorene‐5,8‐diones into larger polyaromatic compounds with extended π‐conjugated systems were explored. The crucial two‐fold transformation of the five‐membered ketone moieties of indeno[2,1‐c]fluorene‐5,8‐diones was based either on a one‐carbon homologation or on a ring‐expansion reaction which eventually enabled syntheses of compounds possessing substituted tribenzo[a,e,l]indeno[1,2,3‐hi]acephenanthrylenes and [5]helicenes scaffolds. The former was prepared by using a reaction sequence based on Ramirez olefination, intramolecular Heck reaction, and intermolecular Suzuki‐Miyaura cross‐coupling, whereas the latter utilized a sequence comprising Büchner−Curtius−Schlotterbeck reaction and intermolecular Suzuki‐Miyaura cross‐coupling. Scholl reaction of selected [5]helicenes yielded planarized polyaromatic compounds with the tribenzo[a,e,l]indeno[1,2,3‐hi]acephenanthrylene scaffold. Where possible, structures of products were confirmed by X‐ray diffraction analyses. Photophysical properties were determined as well. [ABSTRACT FROM AUTHOR]

Attempts to carry out intramolecular annulation of 9,10‐diarylbenzo[h]quinolines and 9,10‐di(hetero)arylphenanthrenes to aromatics with expanded π‐conjugated systems by using different methods are described. The starting compounds (9,10‐diarylbenzo[h]quinolines and 9,10‐di(hetero)arylphenanthrenes) were prepared by C−C bond activation in 1‐azabiphenylene or biphenylene followed by insertion of internal alkynes. Interestingly, unlike in purely carbon‐based aromatics, the course of the annulation turned out to be highly dependent on the structure of maternal compounds. In a handful of cases were obtained the expected or desired products. In others, unexpected rearrangements of the basic molecular frameworks were observed. [ABSTRACT FROM AUTHOR]

This document provides an overview of a special issue published in the Organic and Polymer Chemistry section of the journal Catalysts. The issue includes contributions from 18 members of the journal's Editorial Board and covers a wide range of topics in the fields of homogeneous catalysis, organometallic chemistry, and polymer chemistry. The special issue consists of three review articles and four scientific papers, covering subjects such as gold chemistry, transition metal phosphide nanoparticle catalysts, and cobalt complexes. The document also mentions the importance of communication and academic exchanges among researchers in the field of chemistry. [Extracted from the article]

Transition metal complex catalyzed cocyclotrimerization of 6-alkynylpurines with various diynes enables the preparation of a plethora of substituted 6-arylpurines in good yields. Only CoBr(PPh3)3 showed reasonable activity in cocyclotrimerization of alkynylpurines with dipropargyl ether.

Research has been conducted on the pyridine derivatives from alkynes and nitrile. Results indicate that these derivatives have been formed via azazirconacyclopentadiene reaction with propargyl halides in the presence of CuCl.

Research has been conducted on the cyclic compounds. The formation of these compounds from zirconacycles has been conducted via Michael addition and coupling with an alkenyl iodide moiety in the presence of CuCl.

Benzene derivatives have been made from three alkynes in the presence of a catalytic or stoichiometric amount of transition metal compounds. The reaction of zirconacyclopentadienes with acetylenecarboxylates in the presence of copper chloride is reported. The reaction resulted in the highly selective one-pot formaton of benzene derivatives through the intermolecular coupling of three high yield alkynes.