An acceptorless dehydrogenation of heterocycles catalyzed by frustrated Lewis pairs (FLPs) was developed. Oxidation with concomitant liberation of molecular hydrogen proceeded in high to excellent yields for N-protected indolines as well as four other substrate classes. The mechanism of this unprecedented FLP-catalyzed reaction was investigated by mechanistic studies, characterization of reaction intermediates by NMR spectroscopy and X-ray crystal analysis, and by quantum-mechanical calculations. Hydrogen liberation from the ammonium hydridoborate intermediate is the rate-determining step of the oxidation. The addition of a weaker Lewis acid as a hydride shuttle increased the reaction rate by a factor of 2.28 through a second catalytic cycle.

The borane-catalyzed synthesis of quinoline derivatives bearing tetrasubstituted stereocenters from vinyl anilines has been developed. Mechanistic studies and quantum-mechanical investigations support the hydride abstraction/electrocyclization/hydride addition mechanism. The products were obtained in up to 99 % yield with a diastereoselectivity of >99 % in favour for the 3a-5-cis isomer.

Nuclear magnetic resonance (NMR) spectroscopy is commonly introduced to students in the classroom, but its hands-on use in undergraduate laboratories is far less common. The significant costs to purchase and maintain a traditional high-field NMR spectrometer means that many institutions cannot offer this service to their students. Benchtop NMR spectrometers represent a very powerful alternative at a fraction of the cost and laboratory footprint. However, concerns about resolution and managing second-order effects can hamper its incorporation into the undergraduate curricula. Herein, we describe how resolution at the benchtop level differs from traditional high-field instruments and provide a thorough, tabulated list of 204 molecules which exhibit little to no second-order effects at the lower magnetic fields utilized in benchtop NMR spectroscopy.

Transfer hydrogenation plays an important part in organic chemistry. Recently, strong Lewis acids like B(C6F5)3 have been introduced as a catalyst for these reactions. We successfully employed the Lewis acid (C2F5)3PF2 as a catalyst in the transfer hydrogenation between 1,3,5‐trimethylcyclohexa‐1,4‐diene and 1,1‐diphenylethylene. Surprisingly, the treatment of the diene alone with a catalytic amount of (C2F5)3PF2 led to a quantitative dismutation to mesitylene and 1,3,5‐trimethylcyclohexane. With B(C6F5)3, there was a solvent‐dependency: in CH2Cl2 mainly the dismutation products were obtained, while in toluene the evolution of H2 was observed. Additionally, the catalytic activity of various perfluoroalkylated germanes and silanes was tested.

Mono‐ and dinuclear gold catalysts were investigated in the intermolecular hydroamidation of olefins. Upon activation of [Ph3PAuCl] and [xantphos(AuCl)2] with various silver salts (AgOTf, Ag[BF4], and Ag[SbF6]), diverging reactivity of the resulting cationic gold complexes was observed. It was found that both the binding ability of the counterion and the solvent have a significant impact on the reactivity of the mono‐ and dinuclear complexes.