Photocatalyzed synthesis of unsymmetrical ureas via the oxidative decarboxylation of oxamic acids with PANI-g-C3N4-TiO2 composite under visible light
作者:Liang Wang、Hao Wang、Yaoyao Wang、Minggui Shen、Shubai Li
DOI:10.1016/j.tetlet.2020.151962
日期:2020.6
The synthesis of unsymmetrical ureas via the photocatalyzed oxidative decarboxylation of oxamic acids has been developed. The carbamoyl radicals were generated from oxamic acids in the presence of a hypervalent iodine reagent and the PANI(Polyaniline)-g-C3N4-TiO2 composite under visible light irradiation. The radicals were converted in situ into the corresponding isocyanates, which were then trapped
已经开发了通过光催化的草酰胺酸氧化脱羧合成不对称脲的方法。在高价碘试剂和PANI(聚苯胺)-gC 3 N 4 -TiO 2复合材料的存在下,由草酰胺酸在可见光照射下生成氨基甲酰基自由基。自由基被原位转化进入相应的异氰酸酯,然后被胺捕获,以中等至良好的产率得到相应的产物。该方案避免了直接使用对环境不利的异氰酸酯,并且可以耐受一系列底物。而且,光催化剂可以通过简单的过滤而容易地回收,并且可以在仅轻微降低催化活性的情况下重复使用几次。