title: C–H arylation of unsubstituted furan and thiophene with acceptor bromides: access to donor–acceptor–donor-type building blocks for organic electronics.
abstract: Pd-catalyzed direct arylation (DA) reaction conditions have been established for unsubstituted furan (Fu) and thiophene (Th) with three popular acceptor building blocks to be used in materials for organic electronics, namely 4,7-dibromo-2,1,3-benzothiadiazole (BTBr2), N,N′-dialkylated 2,6-dibromonaphthalene-1,4,5,8-bis(dicarboximide) (NDIBr2), and 1,4-dibromotetrafluorobenzene (F4Br2). Reactions with BTBr2, F4Br2, and NDIBr2 require different solvents to obtain high yields. The use of dimethylacetamide (DMAc) is essential for the successful coupling of BTBr2 and F4Br2, but detrimental for NDIBr2, as the electron-deficient NDI core is prone to nucleophilic core substitution in DMAc as solvent but not in toluene. NDIFu2 is much more planar compared to NDITh2, resulting in an enhanced charge-transfer character, which makes it an interesting building block for conjugated systems designed for organic electronics. This study highlights direct arylation as a simple and inexpensive method to construct a series of important donor–acceptor–donor building blocks to be further used for the preparation of a variety of conjugated materials.
authors.forename: Rukiya
authors.initials: R
authors.lastname: Matsidik
authors.forename: Johannes
authors.initials: J
authors.lastname: Martin
authors.forename: Simon
authors.initials: S
authors.lastname: Schmidt
authors.forename: Johannes
authors.initials: J
authors.lastname: Obermayer
authors.forename: Florian
authors.initials: F
authors.lastname: Lombeck
authors.forename: Fritz
authors.initials: F
authors.lastname: Nübling
authors.forename: Hartmut
authors.initials: H
authors.lastname: Komber
authors.forename: Daniele
authors.initials: D
authors.lastname: Fazzi
authors.forename: Michael
authors.initials: M
authors.lastname: Sommer
mesh_terms: D000081:Acetamides / Q000737:chemistry*; D000478:Alkylation; D052160:Benzothiazoles / Q000737:chemistry*; D001965:Bromides / Q000737:chemistry*; D004583:Electrons; D005464:Fluorobenzenes / Q000737:chemistry*; D005663:Furans / Q000737:chemistry*; D006860:Hydrogen Bonding; D015394:Molecular Structure; D009281:Naphthalenes / Q000737:chemistry*; D013876:Thiophenes / Q000737:chemistry*
chemical_list: C542023:1,4-dibromotetrafluorobenzene; C000600031:2,6-dibromonaphthalene-1,4,5,8-bis(dicarboximide); C000600030:4,7-dibromo-2,1,3-benzothiadiazole; D000081:Acetamides; D052160:Benzothiazoles; D001965:Bromides; D005464:Fluorobenzenes; D005663:Furans; D009281:Naphthalenes; D013876:Thiophenes; C013959:dimethylacetamide