Acid-catalyzed rearrangement of cyclobutanols. Syntheses of chrysenes, cyclopentenophenanthrenes, and diarylmethanes
作者:Edward Lee-Ruff、Alan C. Hopkinson、Hira Kazarians-Moghaddam、Brij Gupta、Morris Katz
DOI:10.1139/v82-026
日期:1982.1.15
Acid-catalyzed reactions of 8-aryl or 8,8-diarylbicyclo[4.2.0]oct-2-en-7-ols lead to tetrahydrophenanthrene derivatives. For example 8-(1-naphthyl)-bicyclo[4.2.0]oct-2-en-7-ols give substituted chrysenes in methanesulphonic acid. In the case of the homologous 7-aryl or 7,7-diarylbicyclo[3.2.0]hept-2-en-6-ols a novel transformation to diarlymethanes is observed. A mechanism is proposed which accounts
Rhenium-catalyzed synthesis of naphthalene derivatives via insertion of aldehydes into a C–H bond
作者:Yoichiro Kuninobu、Yuta Nishina、Kazuhiko Takai
DOI:10.1016/j.tet.2007.05.083
日期:2007.8
A rhenium complex, [ReBr(CO)3(THF)]2, catalyzed reactions of aromatic ketimines and aldehydes with dienophiles, followed by dehydration, to give naphthalene derivatives in good to excellent yields. This reaction proceeds via C–H bond activation, insertion of an aldehyde, intramolecular nucleophilic cyclization, reductive elimination, elimination of aniline and Diels–Alder reaction. After dehydration
Formation of Benzo-Fused Carbocycles by Formal Radical Cyclization onto an Aromatic Ring
作者:Derrick L. J. Clive、Rajesh Sunasee
DOI:10.1021/ol070849l
日期:2007.7.1
An indirect method for effecting radical carbocyclization onto aromatic rings is described. Cross-conjugated dienones such as 13, readily prepared by Birch reduction of aromatic tert-butyl esters, in situ alkylation, and oxidation (10 --> 11 --> 12 --> 13), undergo radicalcyclization; the products (14) are aromatized by silylation, Saegusa oxidation, and treatment with BiCl3.H2O. A noteworthy feature
Formal radical closure onto aromatic rings—a general route to carbocycles
作者:Derrick L. J. Clive、Rajesh Sunasee、Zhenhua Chen
DOI:10.1039/b803308k
日期:——
A general method is described for indirectly effecting radical carbocyclization of an alkyl chain onto an aromatic ring. Birch reductive-alkylation of aromatic tert-butyl esters with α,Ï-dibromides, chromium(VI)-mediated oxidation of the resulting 1,4-dienes and Finkelstein displacement of Brâ with NaI gives cross-conjugated ketones that undergo radical cyclization. The products are easily aromatized to phenols by silylation, Saegusa oxidation and treatment with BiCl3.H2O. A special feature of the route is that it allows attachment of a substituent to the original aromatic ring in place of the phenolic oxygen of the normal product.