A Novel Procedure for the Formation of Isatins <i>via</i> Carbonylation of Lithiated <i>N</i>′-Aryl-<i>N</i>,<i>N</i>-dimethylureas
作者:Keith Smith、Gamal A. El-Hiti、Anthony C. Hawes
DOI:10.1055/s-1999-3085
日期:——
Isatin and substituted isatins can be formed in very good yields from the appropriate N′-(2-bromoaryl)-N,N-dimethylureas via bromine-lithium exchange followed by treatment with carbon monoxide.
Carbonylation of Doubly Lithiated<i>N</i>′-Aryl-<i>N</i>,<i>N</i>-Dimethylureas: A Novel Approach to Isatins via Intramolecular Trapping of Acyllithiums
作者:Keith Smith、Gamal A. El-Hiti、Anthony C. Hawes
DOI:10.1055/s-2003-41019
日期:——
Lithiation of N′-(2-bromoaryl)-N,N-dimethylureas with methyllithium and tert-butyllithium under nitrogen in anhydrous THF at 0 °C gave doubly lithiated arylurea derivatives, which react with carbon monoxide at 0 °C to give isatins in good yields. The scope of the reaction has been demonstrated by application to the synthesis of isatin itself and four substituted isatins bearing alkyl, chloro or fluoro
N'-(2-溴芳基)-N,N-二甲基脲与甲基锂和叔丁基锂在氮气下在无水 THF 中 0 °C 锂化得到双锂化芳基脲衍生物,其在 0 °C 下与一氧化碳反应生成靛红良好的产量。该反应的范围已通过应用于合成靛红本身和四个带有烷基、氯或氟基团的取代的靛红来证明。