Hf(OTf)<sub>4</sub>-Doped Me<sub>3</sub>SiCl-Catalyzed Aminomethylation of Arenes with <i>N</i>,<i>O</i>-Acetals: Facile Approach to Non-Natural Aromatic Amino Acid Precursors
The authors demonstrated a Hf(OTf)4-Me3SiCl-system-catalyzed aminomethylation of an aromatic compound, such as a heterocycle or an electron-rich arene, with several new types of N,O-acetals having both a cyano group and a cyclic amino moiety. This method permits the facile synthesis of artificial aromatic amino acid precursors.
Scope and limitations of reductive amination catalyzed by half-sandwich iridium complexes under mild reaction conditions
作者:Dat P. Nguyen、Rudolph N. Sladek、Loi H. Do
DOI:10.1016/j.tetlet.2020.152196
日期:2020.8
broad assortment of carbonyl-containing compounds. In aqueousmedia, selective reduction of carbonyls to 1° amines was achieved in the absence of acids. Unfortunately, at Ir catalyst concentrations of <1 mM in water, reductive amination efficiency dropped significantly, which suggest that this catalytic methodology might be not suitable for aqueous applications where very low catalyst concentration is
使用甲酸铵作为氮源和氢化物源的半夹心铱配合物可以促进醛和酮向 1°胺的转化。为了优化这种绿色化学合成方法,我们在生理温度 (37 °C) 和环境压力下在常见极性溶剂中测试了各种羰基底物。我们发现,在甲醇中,对于广泛种类的含羰基化合物,可以实现胺对醇/酰胺产物的优异选择性。在水性介质中,在不存在酸的情况下,羰基化合物选择性还原为 1° 胺。不幸的是,在水中 Ir 催化剂浓度 <1 mM 时,还原胺化效率显着下降,