One-Pot CuI/DBU-Catalyzed Carboxylative Cyclization toward Oxazolidinones Using Recyclable Molecular Sieves as Efficient Promoters for Fixation of CO2 in Water Medium

An efficient one-pot synthesis of oxazolidinones was developed through CuI/DBU/MS joint system-catalyzed carboxylative cyclization of arylacetylene, arylaldehyde, and arylamine in water medium under a 1 atm carbon dioxide (CO2) atmosphere. The 4 Å molecular sieves (MSs) were added to improve CO2 capture and facilitate carboxylation to give the products in high yields. The CuI/DBU/MS system is robust and highly effective for the reactions with different substrates, and some target products were obtained in an excellent yield of ∼96%, with no side products in the final step.本研究开发了一种高效的一锅法合成恶唑烷酮类化合物的方法：通过碘化亚铜(CuI)/1,8-二氮杂双环[5.4.0]十一碳-7-烯(DBU)/分子筛(MS)复合体系催化，在1标准大气压二氧化碳(CO₂)氛围的水介质中，实现芳基乙炔、芳基醛与芳基胺的羧化环合反应。体系中添加4埃分子筛(4 Å MS)以强化二氧化碳捕集并促进羧化反应，从而获得高产率的目标产物。该CuI/DBU/MS复合体系稳定性优异，对不同底物参与的反应均具有极高的催化活性；部分目标产物的产率可达约96%，且最终步骤无副产物生成。