Synthesis of pentafluorobenzene-based NHC adducts and their catalytic activity in the microwave-assisted reactions of aldehydes
作者:Evanthia Papadaki、Victoria Magrioti
DOI:10.1016/j.tetlet.2019.151419
日期:2020.1
as standalone organocatalysts in various reactions, mostly using aromatic aldehydes as substrates. We have previously demonstrated the efficiency of azolium-2-carboxylate zwitterions in the hydroxymethylation of aldehydes, especially aliphatic aldehydes, under microwave irradiation. In the present work, we report a series of pentafluorobenzene-based NHC adducts and their efficiency in the hydroxymethylation
N-杂环卡宾(NHC)已广泛用于有机金属化学中作为配体,以及在各种反应中用作独立的有机催化剂,主要使用芳族醛作为底物。先前我们已经证明了在微波辐射下,-2-羧酸偶氮鎓两性离子在醛尤其是脂肪族醛的羟甲基化中的效率。在目前的工作中,我们报告了一系列基于五氟苯的NHC加合物及其在微波辐射下脂族和芳族醛的羟甲基化和自缩合反应中的效率。在反应条件下释放出游离的羧苯甲酸酯,并且1,3-二甲基1,2-(全氟苯基)咪唑烷和1,3-双(2,6-二甲基苯基)-2-(全氟苯基)咪唑烷被证明是最有效的前催化剂。