725213-67-2Relevant academic research and scientific papers
Extended Study of Visible-Light-Induced Photocatalytic [4 + 2] Benzannulation: Synthesis of Polycyclic (Hetero)Aromatics
Chatterjee, Tanmay,Lee, Da Seul,Cho, Eun Jin
, p. 4369 - 4378 (2017/04/28)
Herein we report an extended study of [4 + 2] benzannulation reactions of 2-(hetero)aryl-substituted anilines with alkynes by visible light photocatalysis. The method requires the use of tBuONO as a diazotizing agent and 0.3 mol % of fac-Ir(ppy)3 as a photocatalyst at room temperature. The reaction proceeded in a chemo- and regioselective manner with high functional group tolerance under mild conditions allowing the preparation of a wide variety of polycyclic (hetero)aromatic compounds, including phenanthrenes, in moderate to high yields. This procedure is amenable to gram-scale synthesis of 9-phenylphenanthrene.
Catalyst-free intramolecular formal carbon insertion into σ-C-C bonds: A new approach toward phenanthrols and naphthols
Xia, Ying,Qu, Peiyuan,Liu, Zhenxing,Ge, Rui,Xiao, Qing,Zhang, Yan,Wang, Jianbo
, p. 2543 - 2546 (2013/04/10)
The different reactivity of two kinds of carbonyl groups in keto aldehyde substrates has been exploited for the synthesis of phenanthrols, naphthols, and their heteroatom-containing analogues. Key to this highly efficient and robust methodology is the catalyst-free intramolecular formal diazo carbon insertion of N-tosylhydrazones into keto C-C bonds (see scheme). Copyright
Phenanthrene synthesis by eosin Y-catalyzed, visible light- Induced [4+2] benzannulation of biaryldiazonium salts with alkynes
Xiao, Tiebo,Dong, Xichang,Tang, Yanchi,Zhou, Lei
supporting information, p. 3195 - 3199 (2013/01/16)
A metal-free, visible light-induced [4+2] benzannulation of biaryldiazonium salts with alkynes was developed. With eosin Y as photoredox catalyst, a variety of 9-substituted or 9,10-disubstituted phenanthrenes were obtained via a cascade radical addition and cyclization sequence. Copyright
Palladium-catalyzed intermolecular decarboxylative coupling of 2-phenylbenzoic acids with alkynes via C-H and C-C bond activation
Wang, Congyang,Rakshit, Souvik,Glorius, Frank
supporting information; experimental part, p. 14006 - 14008 (2010/12/24)
A novel protocol for palladium-catalyzed intermolecular formal [4 + 2] annulation of 2-phenylbenzoic acids with alkynes is described. Acridine is shown to be essential for the high reaction efficiency. Phenanthrene derivatives are formed in moderate to good yields without coupling (pseudo)halides or organometallic species.
Chromium-mediated synthesis of polycyclic aromatic compounds from halobiaryls
Kanno, Ken-Ichiro,Liu, Yuanhong,Iesato, Atsushi,Nakajima, Kiyohiko,Takahashi, Tamotsu
, p. 5453 - 5456 (2007/10/03)
(Chemical Equation Presented) Reaction of 2,2′-dihalobiphenyl with butyllithium followed by the addition of chromium(III) chloride and alkynes afforded the corresponding phenanthrene derivatives via formal [4 + 2] cycloaddition. A variety of alkynes could be used for this reaction, such as alkyl, aryl, silyl, and alkoxycarbonyl alkynes. Repetitive process of the reaction gave more extended polycyclic compounds such as benzo[g]chrysene and azacyclopentaphenalene derivatives.
Synthesis of polycyclic aromatics and heteroaromatics via electrophilic cyclization
Yao, Tuanli,Campo, Marino A.,Larock, Richard C.
, p. 3511 - 3517 (2007/10/03)
(Chemical Equation Presented) A variety of substituted polycyclic aromatics are readily prepared in good to excellent yields under very mild reaction conditions by the reaction of 2-(1-alkynyl)biphenyls with ICl, I2, NBS, and p-O2NC
Synthesis of polycyclic aromatic iodides via ICI-induced intramolecular cyclization
Yao, Tuanli,Campo, Marino A.,Larock, Richard C.
, p. 2677 - 2680 (2007/10/03)
The reaction of 2-(arylethynyl)biphenyls with ICI at -78°C affords substituted polycyclic aromatic iodides in good to excellent yields. The aryl substituents can be either electron-donating or electron-withdrawing groups such as OMe, Me, CHO, CO2Et or NO2 groups. This chemistry has been successfully extended to systems containing a variety of polycyclic and heterocyclic rings.
