Synthesis of Oxazolidinones from Epoxides and Isocyanates Catalysed by Aluminium Heteroscorpionate Complexes
作者:José A. Castro-Osma、Amy Earlam、Agustín Lara-Sánchez、Antonio Otero、Michael North
DOI:10.1002/cctc.201600407
日期:2016.6.21
of an aluminium(heteroscorpionate) complex and tetrabutylammonium bromide acts as a highly efficient catalyst system for the synthesis of oxazolidinones from epoxides and isocyanates. Twenty two complexes were tested derived from a range of bispyrazole ligands and containing 1–3 aluminium atoms per complex. The optimal catalyst was found to be a bimetallic complex of a thioacetamidate ligand. Under
铝(杂蝎子酸盐)配合物和四丁基溴化铵的组合用作从环氧化物和异氰酸酯合成恶唑烷酮的高效催化剂体系。测试了22种配合物,它们来自一系列的联吡唑配体,每个配合物含有1-3个铝原子。发现最佳催化剂是硫代乙酰胺酸酯配体的双金属配合物。在最佳反应条件下(在80°C的甲苯中使用5 mol%的铝催化剂和四丁基溴化铵助催化剂在24°C下反应),六种环氧化物与六种芳族异氰酸酯反应,得到25种恶唑烷酮,收率中等至优异,显示了广泛的底物范围。反应的区域化学(产生3,4-或3,