Synthesis of indenones via palladium-catalyzed annulation of internal alkynes
摘要:
A number of 2,3-disubstituted 1-indenones have been prepared in fair to good yields by treating o-iodo- or o-bromobenzaldehyde with various internal alkynes in the presence of a palladium catalyst. Synthetically, the methodology provides an especially convenient route to stable hindered indenones containing aryl, silyl, and tert-alkyl groups. The reaction is believed to proceed through a palladium-(IV) intermediate, and the regiochemistry of the reaction is controlled sterically.
Carbopalladation of Nitriles: Synthesis of 2,3-Diarylindenones and Polycyclic Aromatic Ketones by the Pd-Catalyzed Annulation of Alkynes and Bicyclic Alkenes by 2-Iodoarenenitriles
作者:Alexandre A. Pletnev、Qingping Tian、Richard C. Larock
DOI:10.1021/jo026178g
日期:2002.12.1
represents one of the first examples of the addition of an organopalladium moiety to the carbon-nitrogentriplebond of a nitrile. The reaction is compatible with a number of functional groups. A reaction mechanism, as well as a model accounting for the electronic effects of substituents on the aromatic ring of the nitrile, is proposed.
Gold-Catalyzed Ammonium Acetate Assisted Cascade Cyclization of 2-Alkynylarylketones
作者:Maciej E. Domaradzki、Yuhua Long、Zhigang She、Xiaochen Liu、Gan Zhang、Yu Chen
DOI:10.1021/acs.joc.5b01939
日期:2015.11.20
An ammonium acetate assisted gold-catalyzedcascadecyclization reaction of 2-alkynylarylketones is described. Under the reported conditions, a gold-catalyzed intramolecular cyclization of 2-alkynylarylketones takes place through two competing reaction mechanisms—a 5-exo-dig or a 6-endo-dig cyclization—leading to two regioisomeric intermediates: isobenzofuranium or isobenzopyrylium. In the presence
Synthesis of Indenyl Triazenes by Rhodium-Catalyzed Annulation Reactions
作者:Carl T. Bormann、Florian G. Abela、Rosario Scopelliti、Farzaneh Fadaei-Tirani、Kay Severin
DOI:10.1002/ejoc.202000195
日期:2020.4.16
Rh‐catalyzed [3+2] annulation reactions of arylboronic acid derivatives and alkynyl triazenes, which provide access to functionalized indenyl triazenes, are described. The regioselectivity of the annulations is mostly high, but strongly dependent on the substituents on the alkyne