Carbon Dioxide as the C1 Source for Direct C−H Functionalization of Aromatic Heterocycles
作者:Oleg Vechorkin、Nathalie Hirt、Xile Hu
DOI:10.1021/ol101450u
日期:2010.8.6
A simple and straightforward method has been developed for the direct carboxylation of aromatic heterocylces such as oxazoles, thiazoles, and oxadiazoles using CO(2) as the C1 source. The reactions require no metal catalyst and only Cs(2)CO(3) as the base. A good functional group tolerance is achieved.
I<sub>2</sub>-Promoted formal [3+2] cycloaddition of α-methylenyl isocyanides with methyl ketones: a route to 2,5-disubstituted oxazoles
An I2-promoted formal [3+2] cycloaddition for access to oxazoles has been demonstrated. This is the first example of a Lewis acid-promoted formal [3+2] cycloaddition of isocyanides with methyl ketones involves...