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

Abstract

A new class of π-conjugated polycyclic hydrocarbons that promises interesting electronic properties is presented. The synthesis and extension of the S,N-heteroacene series consisting of only five-membered heterocyclic rings up to a very long, stable, and still soluble decacene SN10 is realized by multiple Pd-catalyzed aminations of halogenated thiophene precursors as key reactions. These novel heteroacenes were characterized by optical spectroscopy and electrochemistry providing interesting structure-property relationships. Nearly complete bond-length equalization in the inner part of the conjugated backbone and an unusual herringbone packing in the solid state underline the structural features of these novel systems.

Aryl(triethyl)silanes for Biaryl and Teraryl Synthesis by Copper(II)‐Catalyzed Cross‐Coupling Reaction

“…[17] We focused on at hiophene motif as an electron-rich aryl group,and examined the double cross-coupling reaction of 2,5-bis(triethylsilyl)thiophene (3b) and its 3,4-ethylenedioxy analogue 3c with iodoarene 4. [18] To our delight, they gave the corresponding products bearing alternately an electron-rich thiophene ring and electrondeficient aryl group like p-cyanophenyl (4m)ingood to high yields (Entries 1-4). Thef act that only as mall amount of mono-coupled products accompanied the reaction indicates that the mono-coupled arylsilanes are more reactive than the starting disilylarenes.2 ,5-Bis(triethylsilyl)furan (3d)c ould also be used (Entry 5).…”

Ladder‐Type Heteroarene‐Based Organic Semiconductors

“…Recently, Bäuerle et al. devised a series of ladder‐type S,N‐heteroarenes ( 27 – 29 ) with up to ten fused thiophene and pyrrole rings, which were synthesized from their halogenated thiophene precursors by multiple Pd‐catalyzed aminations . These S,N‐heteroarenes exhibited good solubility, excellent stability, and a herringbone packing motif, indicative of potential applications in organic electronic devices …”

Sulfur‐Containing Bent N‐Heteroacenes

“…Acenes have made a significant impact on organic functional materials due to their unique optical and electrical properties, especially as activated layers in organic field effect transistors (OFETs), organic light‐emitting diodes (OLEDs), and organic photovoltaics (OPVs) . In recent years, synthetic chemists have devoted substantial efforts to studying linear azaacenes .…”

“…Acenesh ave made as ignificant impacto no rganic functional materials due to their unique optical and electrical properties, especially as activated layersi no rganic field effect transistors (OFETs), organic light-emitting diodes (OLEDs), and organic photovoltaics (OPVs). [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] In recent years, synthetic chemists have devoted substantial efforts to studyinglinear azaacenes. [1,4,[16][17][18][19][20][21][22][23][24] However,w ith the molecular length increasing, its stability diminishes, and even decomposes.…”