- Aromatic Metamorphosis of Dibenzofurans into Triphenylenes Starting with Nickel-Catalyzed Ring-Opening C-O Arylation
-
A new class of aromatic metamorphosis has been developed in which dibenzofurans were converted into triphenylenes. This transformation is composed of three successive operations: (1) nickel-catalyzed ring-opening C-O bond arylation with arylmagnesium bromides, (2) trifluoromethanesulfonylation (triflation) of the resulting hydroxy moiety with Tf2O, and (3) palladium-catalyzed or photoinduced ring closure. In the last ring-closing step, the photoinduced process has proven to be more productive than the palladium-catalyzed one. By employing π-extended dinaphthofuran as the substrate, dorsally benzo-fused [5]helicene was obtained in a satisfactory yield.
- Kurata, Yuto,Otsuka, Shinya,Fukui, Norihito,Nogi, Keisuke,Yorimitsu, Hideki,Osuka, Atsuhiro
-
supporting information
p. 1274 - 1277
(2017/03/22)
-
- Synthesis of Triphenylenes Starting from 2-Iodobiphenyls and Iodobenzenes via Palladium-Catalyzed Dual C-H Activation and Double C-C Bond Formation
-
A novel and facile approach for the synthesis of triphenylenes has been developed via palladium-catalyzed coupling of 2-iodobiphenyls and iodobenzenes. The reaction involves dual palladium-catalyzed C-H activations and double palladium-catalyzed C-C bond formations. A range of unsymmetrically functionalized triphenylenes can be synthesized with the reaction. The approach features readily available starting materials, high atom- and step-economy, and access to various unsymmetrically functionalized triphenylenes.
- Zhang, Yanghui,Pan, Shulei,Jiang, Hang,Zhang, Yu,Chen, Dushen
-
p. 5192 - 5195
(2016/11/02)
-
- Palladium-Assisted "Aromatic Metamorphosis" of Dibenzothiophenes into Triphenylenes
-
Abstract Two new palladium-catalyzed reactions of aromatic sulfur compounds enabled the conversion of dibenzothiophenes into triphenylenes in four steps. This transformation of one aromatic framework into another consists of 1) 4-chlorobutylation of the dibenzothiophene to form the corresponding sulfonium salt, 2) palladium-catalyzed arylative ring opening of the sulfonium salt with a sodium tetraarylborate, 3) an intramolecular SN2 reaction to form a teraryl sulfonium salt, and 4) palladium-catalyzed intramolecular C-S/C-H coupling through electrophilic palladation. Symmetrical as well as unsymmetrical triphenylenes of interest were synthesized in a tailor-made fashion in satisfactory overall yields. A change of heart: The invention of two palladium-catalyzed arylation reactions of organosulfur compounds enabled the transformation of dibenzothiophenes into triphenylenes and thus a fundamental change in the core aromatic structure (see scheme). Both symmetrical and unsymmetrical triphenylenes were synthesized in a tailor-made fashion in satisfactory overall yield.
- Vasu, Dhananjayan,Yorimitsu, Hideki,Osuka, Atsuhiro
-
p. 7162 - 7166
(2015/06/08)
-
- SINGLE TRIPHENYLENE CHROMOPHORES IN PHOSPHORESCENT LIGHT EMITTING DIODES
-
Novel triphenylene compounds are provided. Specific examples include multi-aryl-substituted triphenylenes. A preferred group of compounds are triphenylenes that are substituted with a non-fused aryl group having one or more meta-substituents, where each meta-substituent is a non-fused aryl group optionally substituted with further substituents selected from the group consisting of non-fused aryl groups and alkyl groups. A further preferred group of compounds are triphenylenes that are substituted with a non-fused heteroaryl group having one or more meta-substituents, where each meta-substituent is a non-fused aryl or heteroaryl group optionally substituted with further substituents selected from the group consisting of non-fused aryl groups, non-fused heteroaryl groups, and alkyl groups. Some high triplet energy analogs are expected to work with deep blue phosphorescent dopants. The compounds may be useful in phosphorescent organic light emitting devices. Also provided is an organic electroluminescent device comprising an anode, a cathode, and an emissive layer between the anode and the cathode, the emissive layer comprising a phosphorescent material and a compound having a repeat unit, the repeat unit containing a triphenylene moiety.
- -
-
Page/Page column 48-49
(2009/04/25)
-