Highly Efficient Route to Fused Polycyclic Aromatics via Palladium-Catalyzed Aryne Annulation by Aryl Halides
作者:Zhijian Liu、Richard C. Larock
DOI:10.1021/jo0619534
日期:2007.1.1
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
Synthesis of Fluoren-9-ones by the Palladium-Catalyzed Cyclocarbonylation of <i>o</i>-Halobiaryls
作者:Marino A. Campo、Richard C. Larock
DOI:10.1021/jo020140m
日期:2002.8.1
The synthesis of various substituted fluoren-9-ones has been accomplished by the palladium-catalyzed cyclocarbonylation of o-halobiaryls. The cyclocarbonylation of 4'-substituted 2-iodobiphenyls produces very high yields of 2-substituted fluoren-9-ones bearing either electron-donating or electron-withdrawing substituents. 3'-Substituted 2-iodobiphenyls afford 3-substituted fluoren-9-ones in excellent
Synthesis of Polycyclic Aromatic Iodides via ICl-Induced Intramolecular Cyclization
作者:Tuanli Yao、Marino A. Campo、Richard C. Larock
DOI:10.1021/ol049161o
日期:2004.8.1
The reaction of 2-(arylethynyl)biphenyls with ICl at -78 degrees 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, CO(2)Et or NO(2) groups. This chemistry has been successfully extended to systems containing a variety of polycyclic and heterocyclic rings. [reaction:
Aryl to Aryl Palladium Migration in the Heck and Suzuki Coupling of <i>o</i>-Halobiaryls
作者:Marino A. Campo、Haiming Zhang、Tuanli Yao、Abdellatif Ibdah、Ryan D. McCulla、Qinhua Huang、Jian Zhao、William S. Jenks、Richard C. Larock
DOI:10.1021/ja069238z
日期:2007.5.1
A novel 1,4-palladium migration between the o- and o'-positions of biaryls has been observed in organopalladium intermediates derived from o-halobiaryls. The organopalladium intermediates generated by this migration have been trapped either by a Heck reaction employing ethyl acrylate or by Suzuki cross-coupling using arylboronic acids. This palladium migration can be activated or deactivated by choosing the appropriate reaction conditions. Chemical and computational evidence supports the presence of an equilibrium that correlates with the C-H acidity of the available arene positions.
Novel 1,4-Palladium Migration in Organopalladium Intermediates Derived from <i>o</i>-Iodobiaryls
作者:Marino A. Campo、Richard C. Larock
DOI:10.1021/ja027548l
日期:2002.12.1
A novel 1,4-palladium migration in organopalladium intermediates derived from o-iodobiaryls has been observed under modified Heck reaction conditions. This migration process can be switched "on" or "off" by simply choosing the appropriate reaction conditions.