Ethyl-Zinc(II)-Cation Equivalents: Synthesis and Hydroamination Catalysis.

ABSTRACT

Ion-like ethylzinc(II) compounds with weakly coordinating aluminates [Al(OR(F))4](-) and [(R(F)O)3Al-F-Al(OR(F))3](-) (R(F)=C(CF3)3) were synthesized in a one-pot reaction and fully characterized by single-crystal X-ray diffraction, NMR and vibrational spectroscopy, and by quantum chemical calculations. The catalytic activity of ion-like Et-Zn[Al(OR(F))4] in intermolecular hydroamination and in the unusual double hydroamination of anilines and alkynes was investigated. Favorable performance was also found in comparison to the Et2Zn/[PhNMe2H](+)[B(C6F5)4](-) system generated in situ at lower catalyst loadings of 2.5 mol %.