Synthesis of Nitrogen-Bridged Terthiophenes by Tandem Buchwald–Hartwig Coupling and Their Properties

Abstract

The first synthesis of nitrogen-bridged terthiophenes (NBTTs) has been achieved by a tandem Buchwald-Hartwig coupling of 3,3',3",4'-tetrabromo-2,2':5',2"-terthiophene. Several NBTT derivatives bearing aryl or alkyl moieties on the N-atoms could be synthesized. Their fundamental electrochemical characteristics and HOMO-LUMO levels were found to be influenced by the substituents on the N-atoms.

Fused Thiophene‐Pyrrole‐Containing Ring Systems up to a Heterodecacene

“…[6] Mixed five-membered ring heteroacenes consisting of fused thiophene (X = S) and pyrrole units (X = NR), so-called S,N-heteroacenes,a re advantageous over thienoacenes [6] because solubilizing substituents can be attached at the nitrogen atoms.W ithin the series of pure S,N-heteroacenes,dithieno[3,2-b:2',3'-d]pyrrole (DTP) has been known for some time, [7] while different Nalkylated S,N-heteropentacenes SN5 were presented only recently. [8] We pursued as imilar concept and reported acceptor-functionalized S,N-heteropentacenes for application in different types of organic solar cells.T hus,a cceptorsubstituted SN5 derivatives achieved efficiencies of as much as 6.5 %i nv acuum-processed solar cells, [9] up to 4.9 %i n solution-processed solar cells, [10] and up to 10.3 %when used as hole transporters in Perovskite cells. [11] Thetodate longest S,N-heteroacene,h eterohexacene SN6,w as recently presented by our group and showed interesting optoelectronic properties as well as good charge-carrier mobility.…”

Dithienosilolothiophene: A New Polyfused Donor for Organic Electronics

“…Several reaction conditions were tested using various palladium catalysts, reaction solvents, times, and temperatures, but each time, complex reaction mixtures with a significant amount of deiodated thiophene derivatives were recovered. Therefore, we adapted our approach and synthesized the tetrabrominated terthiophene intermediate (3) following the literature procedure published by Mitsudo et al 11 The synthetic pathway toward the novel distannylated dithienosilolothiophene (6) monomer is outlined in Scheme 1.…”

Sequentially Palladium-Catalyzed Processes in One-Pot Syntheses of Heterocycles

“…The method uses 2,2′-dihalobiphenyls and primary amines for the synthesis of multisubstituted carbazoles 22 that possess intriguing optical properties (Scheme 14). The methodology has then been applied to the synthesis of different compound classes, for instance to the synthesis of diazacarbazoles [95], ladder-type π-conjugated heteroacenes [96], dithienopyrroles [97][98][99], and to the synthesis of the phenothiazine backbone of promazines [100]. The method has also been employed in the synthesis of dithienothiazines 23 that possess interesting electronic properties involving reversible oxidation and can therefore be regarded as new donors for functional π-systems (Scheme 15, Fang and Lautens reported an assisted tandem catalysis involving an intramolecular palladium-catalyzed Buchwald-Hartwig amination and intermolecular Suzuki-Miyaura coupling [103].…”