<i>N</i>-Methylacridinium Salts: Carbon Lewis Acids in Frustrated Lewis Pairs for σ-Bond Activation and Catalytic Reductions
作者:Ewan R. Clark、Michael J. Ingleson
DOI:10.1002/anie.201406122
日期:2014.10.13
N‐methylacridinium salts are Lewis acids with high hydride ion affinity but low oxophilicity. The cation forms a Lewis adduct with 4‐(N,N‐dimethylamino)pyridine but a frustrated Lewis pair (FLP) with the weaker base 2,6‐lutidine which activates H2, even in the presence of H2O. Anion effects dominate reactivity, with both solubility and rate of H2 cleavage showing marked anion dependency. With the optimal
N-甲基ac鎓盐是路易斯酸,具有高氢化物离子亲和力但亲氧性低。阳离子与4-(N,N-二甲基氨基)吡啶形成路易斯加合物,而沮丧的路易斯对(FLP)与较弱的2,6-二甲基吡啶碱即使在存在H 2 O的情况下也能激活H 2。阴离子作用H 2的溶解度和H 2裂解速率均显示出显着的阴离子依赖性。在最佳阴离子的作用下,N-甲基ac鎓盐分别催化亚胺通过胺-硼烷和硅烷的还原转移氢化和氢化硅烷化。此外,相同的盐对于硅烷催化的醇(伯,仲,叔和ArOH)的催化脱氢硅烷化反应具有活性,而没有观察到烷烃过度还原。