Catalytic Fixation of Carbon Dioxide Driven by Photoenergy

二氧化碳（CO2）是一种环境友好型原料，其作为可持续碳源的利用是均相过渡金属催化的重要挑战之一。最近，我们研究了镍催化芳酰氯的羧化反应。以锰粉为还原剂，在CO2 （1atm）室温下进行反应。由相应的芳烃氯化物可得到各种苯甲酸衍生物，收率较高。此外，我们最近开发了钴催化与二氧化碳的丙炔乙酸酯羧基化使用锰粉。各种丙炔乙酸酯，特别是末端炔碳上带有三甲基硅基的丙炔乙酸酯，以优异的收率和较高的收率转化为相应的羧酸，具有良好的区域选择性。

Carbon dioxide (CO2) is environmentally friendly raw material and its utilization as sustainable carbon source is one of the most important challenges in homogeneous transition-metal catalysis. Recently, we developed the nickel-catalyzed carboxylation of aryl chlorides. The reactions proceeded under CO2 (1 atm) at room temperature with manganese powder as a reducing reagent. Various benzoic acid derivatives could be obtained from the corresponding aryl chlorides in good to high yields. In addition, we have recently developed the cobalt-catalyzed carboxylation of propargyl acetates with CO2 employing manganese powder. Various propargyl acetates especially bearing trimethylsilyl group on the terminal alkyne carbon were converted to the corresponding carboxylic acids in good to high yields with perfect regioselectivity.