1705-84-6Relevant articles and documents
Highly efficient route to fused polycyclic aromatics via palladium-catalyzed aryne annulation by aryl halides
Liu, Zhijian,Larock, Richard C.
, p. 223 - 232 (2007)
Polycyclic aromatic and heteroaromatic hydrocarbons have been synthesized in high yield by two different processes involving the Pd-catalyzed annulation of arynes. The first process involves a Pd-catalyzed annulation of arynes by 2-halobiaryls and related vinylic halides. The second process utilizes a Pd-catalyzed double annulation of arynes by simple aryl halides. Both processes appear to involve the catalytic, stepwise coupling of two very reactive substrates, an aryne and an organopalladium species, to generate excellent yields of cross-coupled products.
Proton-catalyzed, silane-fueled friedel-crafts coupling of fluoroarenes
Allemann, Oliver,Duttwyler, Simon,Romanato, Paola,Baldridge, Kim K.,Siegel, Jay S.
, p. 574 - 577 (2011)
The venerable Friedel-Crafts reaction appends alkyl or acyl groups to aromatic rings through alkyl or acyl cation equivalents typically generated by Lewis acids. We show that phenyl cation. Friedel-Crafts reaction to intramolecular aryl couplings. The enabling feature of this reaction is the exchange of carbon-fluorine for silicon-fluorine bond enthalpies; the reaction is activated by an intermediate silyl cation. Catalytic quantities of protons or silyl cations paired with weakly coordinating carborane counterions initiate the reactions, after which proton transfer in the final aromatization step regenerates the active silyl cation species by protodesilylation of a quaternary silane. The methodology allows the high-yield formation of a range of tailored polycyclic aromatic hydrocarbons and graphene fragments.
Synthesis of triphenylene derivatives by Pd-catalyzed Suzuki coupling/intramolecular C–H activation between arylboronic acids and dibromobiphenyls
Tu, Jingxuan,Li, Gaoqiang,Zhao, Xiaoqian,Xu, Feng
supporting information, p. 44 - 47 (2018/11/30)
An efficient and regioselective synthesis of functionalized triphenylenes via palladium-catalyzed Suzuki-Miyaura coupling and subsequent intramolecular C–H activation between arylboronic acids and dibromobiphenyls was developed. This methodology showed excellent atomic economy and regiospecificity as well as synthetic feasibility of unsymmetrical triphenylenes.
Palladium-Assisted "Aromatic Metamorphosis" of Dibenzothiophenes into Triphenylenes
Vasu, Dhananjayan,Yorimitsu, Hideki,Osuka, Atsuhiro
supporting information, p. 7162 - 7166 (2015/06/08)
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.