Dibenzopentalenes from B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>-Induced Cyclization Reactions of 1,2-Bis(phenylethynyl)benzenes
作者:Chao Chen、Marcel Harhausen、René Liedtke、Kathrin Bussmann、Aiko Fukazawa、Shigehiro Yamaguchi、Jeffrey L. Petersen、Constantin G. Daniliuc、Roland Fröhlich、Gerald Kehr、Gerhard Erker
DOI:10.1002/anie.201300871
日期:2013.6.3
'Lene' and mean: The strong Lewis acid B(C6F5)3 efficiently converts some bis(arylethynyl)benzenes into dibenzopentalenes through a series of Lewis acid induced cyclizationreactions at room temperature. Thus the reaction has the potential to be useful in the synthesis of substituted dibenzopentalene derivatives which are difficult to make by conventional means.
“ Lene”和均值:强路易斯酸B(C 6 F 5)3通过一系列路易斯酸在室温下诱导的环化反应,有效地将一些双(芳基乙炔基)苯转化为二苯并戊烯。因此,该反应具有用于合成取代的二苯并戊烯衍生物的潜力,这是用常规方法难以制备的。
Synthesis of Fulvene Vinyl Ethers by Gold Catalysis
作者:Alexander Ahrens、Julia Schwarz、Danilo M. Lustosa、Raheleh Pourkaveh、Marvin Hoffmann、Frank Rominger、Matthias Rudolph、Andreas Dreuw、A. Stephen K. Hashmi
DOI:10.1002/chem.202000338
日期:2020.4.21
5-endo-dig-cyclization in these transformations, providing fulvene derivatives. With respect to the functional-group tolerance, aryl fluorides, chlorides, bromides, and ethers are tolerated. Furthermore, the mechanism and selectivity are put to scrutiny by experimental studies and a thermodynamic analysis of the product. Additionally, 6-(vinyloxy)fulvenes are a hitherto unknown class of compounds. Their reactivity
Aromatic polyfluoro-compounds. Part LIV. Copper-assisted nucleophilic displacement reactions of pentafluorohalogenobenzenes
作者:J. Burden、P. L. Coe、C. R. Marsh、J. C. Tatlow
DOI:10.1039/p19720000763
日期:——
Copper-assisted nucleophilic displacement reactions of pentafluorohalogenobenzenes have been investigated; in some cases exclusive halogen replacement occurs, and in others fluorine displacement and halogen reduction are observed. The effects of solvent and added ligands, notably thiourea, on the course of the reaction have been studied and a theory developed to explain the results observed.
Borylative cyclisation of diynes using BCl<sub>3</sub> and borocations
作者:Andrew J. Warner、Kieron M. Enright、John M. Cole、Kang Yuan、John S. McGough、Michael J. Ingleson
DOI:10.1039/c9ob00991d
日期:——
The borylative cyclisation of 1,2-dialkynyl benzenes with BCl3 leads to dibenzopentalenes (via intramolecular SEAr) or benzofulvenes (via chloride addition) depending on substituents, with stabilised vinyl cation intermediates (e.g. with a p-MeO-C6H4-group) favouring the latter. The use of borocations leads to more selective dibenzopentalene formation, while other diyne frameworks undergo intramolecular
1,2-二炔基苯与BCl 3的硼化环化反应会生成二苯并戊烯(通过分子内S E Ar)或苯并富勒烯(通过氯化物加成),具体取决于取代基,并带有稳定的乙烯基阳离子中间体(例如,对-MeO-C 6 H 4-组)赞成后者。使用borocations引线以更有选择性dibenzopentalene形成,而其他二炔框架经历分子内小号Ë用Ar选择性甚至p -MeO基团。
Bergman Cyclization of Fluorinated Benzo-Fused Enediynes to Naphthalene Derivatives: Syntheses and Structures
作者:Christopher M. Kane、Tiffany B. Meyers、Xin Yu、Michael Gerken、Markus Etzkorn
DOI:10.1002/ejoc.201001747
日期:2011.6
Fluorinated naphthalenederivatives were prepared by Bergman cyclization of fluorinated benzo-fused enediynes. This route provides access to the aromatic target compounds in a two-step procedure from commercially available precursors, via a Sonogashira cross-coupling and a subsequent, thermally initiated Bergman cyclization. Crystal structures of six fluorinated benzo-enediynes and three fluorinated