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The synthesis of 1,2′-biazulenes was established by palladium-catalyzed homocoupling reactions of the corresponding 1-haloazulenes in the presence of ferrocene. The optical properties of the novel 1,2′-biazulenes were investigated by UV/Vis spectroscopy and theoretical calculations. The redox behaviors of 1,2′-biazulenes were also examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV).

Preparation of 2- and 6-thienylazulene derivatives was established by the palladium-catalyzed direct cross-coupling reaction of 2- and 6-haloazulenes with the corresponding thiophene derivatives in good yield. Several thienylazulene derivatives were also used in the reaction with 2-chloroazulene derivatives in the presence of the palladium-catalyst to afford the thiophene derivatives with two azulene functions in good yield.

2- and 6-arylazulene substrates (III) and (VIII) are prepared by cross-coupling of aryl halides (I) with 2- or 6-haloazulene (II) and (VII).

Synthesis of 2,2′-diamino-1,1′-biazulene derivatives 5 and 9–11 was established by copper-catalyzed homocoupling reaction of the corresponding 2-aminoazulenes 3 and 6–8. The palladium-catalyzed cro...

The synthesis of 1-methylthio- and 1,3-bis(methylthio)azulenes with an electron-donating group at the 6-position as well as their transformation into the corresponding novel 1,1′-bisazulene derivatives [cf.

Acetylene derivatives with azulenyl groups at both c-atoms are prepared by palladium-catalyzed alkynylation under Sonogashira—Hagihara conditions.

Title compounds (III), (V), and (VII) are prepared using Sonogashira—Hagihara conditions and show the small HOMO-LUMO energy gaps due to their effective π-conjugation.

6,13-Diiododibenzo[a,h]anthracene and 5,8-diiodopicene were synthesized by AuCl-catalyzed double cyclization. The highly selective reaction yielded a new class of peri-halogenated fused aromatics.

For the first time, an efficient synthesis of 2-heteroarylazulene derivatives through electrophilic substitution without using a transition-metal catalyst is established.

Novel bisimide-fused acenes were synthesized viabismuth triflate mediated double-cyclization reaction of acid chlorides and isocyanates. Their optical and electrical properties revealed significantly smaller HOMO–LUMO gaps compared with those of their parent acenes. Fabricated OFET based on tetracene bisimide showed n-type OFET outputs.

4,11-Ethano-4,11-dihydro-2H-anthra[2,3-c]pyrroles (IV) and the corresponding thiophene (VI) are prepared, and their thermogravimetric behavior is studied.

The title carbocation, generated from 1,1-ethylene-1,6-dihydroazulene and trityl tetrafluoroborate in deuterated acetonitrile at −20 °C, was characterized by means of low temperature NMR spectroscopy, and was found to undergo expansion of the cyclopropane ring at elevated temperature and to react with nucleophiles to give the addition products at the cyclopropane methylene carbon.

The first versatile organometallic reagents of azulenes, 6-(tri-n-butylstannyl)azulenes, have been prepared by a Pd(0)-catalyzed direct stannylation of 6-bromoazulenes with bis(tri-n-butyltin). We demonstrate herein the utility of the reagents in the Stille cross-coupling reaction with aryl and azulenyl halides to afford 6-aryl- and biazulenes in good yield.

Soluble precursors of β-, meso-unsubstituted mono-, di- and tribenzoporphyrins were prepared by the reaction of dimethylbicyclo[2.2.2]octadiene-fused pyrrole with appropriate p-free pyrroles. The retro Diels-Alder reaction of these precursors afforded the corresponding benzoporphyrins in quantitative yields.

Solution processable organic semiconducting small molecules are desirable for the manufacture of low-cost, large-area electronic products on flexible substrates. This article provides an overview of recent progress in OFETs based on solution processable small molecules that can be converted to insoluble organic semiconducting materials on films by thermal or photochemical removal of leaving groups after fabrication of the film.

Several azulene-substituted thioketones, 1-thiobenzoylazulene (1a) and di(1-azulenyl) thioketone (2a) and their derivatives (1b and 2b-d) with alkyl substituents on each azulene ring, were prepared and their intramolecular pericyclization reaction was examined. The thioketones with a 3-alkyl substituent on each azulene ring exhibited the presumed pericyclization reaction under thermal and acid-catalyzed conditions, although the cases of the 1-azulenyl thioketones without the 3-alkyl substituents afforded a complex mixture under similar conditions. The intramolecular reaction following the intramolecular hydrogen transfer afforded the products 13b, 14b, and 14c. The products 13b and 14b were converted into the corresponding cations 18(+) and 19(+), which have structural similarity with that of the phenalenyl cation. These cations exhibited the expected two-step reduction waves upon CV, although the ESR analysis revealed that the neutral radical state did not have the presumed high stability.

This paper describes an efficient preparation of 2-azulenylboronate ( 6 ) starting from 2-iodoazulene by halogen–metal exchange reaction using n -BuLi and subsequent quenching with 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. The boronate 6 has been found to undergo Pd-catalyzed Miyaura-Suzuki cross-coupling reaction with a range of aryl bromides including aromatic poly bromides utilizing Pd 2 (dba) 3 –P( t -Bu) 3 as a catalyst and establishes a strategy to produce novel poly(2-azulenyl)benzenes, some of which are found to be insoluble in common organic solvents, however. The redox behavior of 2-arylazulenes and poly(2-azulenyl)benzenes was examined by cyclic voltammetry (CV) and compared with those of 6-azulenylbenzene derivatives reported previously.

Amination of 2-substituted azulene was carefully examined using several types of amines, and the scope and limitation of substrates and reagents in these direct nucleophilic aminations were found. The synthesis of 2-aminoazulenes was successfully achieved by the reaction of 2-bromoazulene with several amines via palladium-catalyzed amination.