Zusammenfassung
Cationic Lewis acids (LAs) are gaining interest as targets for frustrated Lewis pair (FLP)-mediated catalysis. Unlike neutral boranes, which are the most prevalent LAs for FLP hydrogenations, the Lewis acidity of cations can be tuned through modulation of the counteranion; however, detailed studies on such anion effects are currently lacking in the literature. Herein, we present experimental and ...
Zusammenfassung
Cationic Lewis acids (LAs) are gaining interest as targets for frustrated Lewis pair (FLP)-mediated catalysis. Unlike neutral boranes, which are the most prevalent LAs for FLP hydrogenations, the Lewis acidity of cations can be tuned through modulation of the counteranion; however, detailed studies on such anion effects are currently lacking in the literature. Herein, we present experimental and computational studies which probe the mechanism of H-2 activation using iPr(3)SnOTf (1-OTf) in conjunction with a coordinating (quinuclidine; qui) and non-coordinating (2,4,6-collidine; col) base and compare its reactivity with {iPr,Sn.base}{Al[OC(CF3)(3)](4)} (base = qui/col) systems which lack a coordinating anion to investigate the active species responsible for H-2 activation and hence resolve any mechanistic roles for OTf- in the iPr(3)SnOTf-mediated pathway.