Practical electrochemical hydrogenation of nitriles at the nickel foam cathode.

We report a scalable hydrogenation method for nitriles based on cost-effective materials in a very simple two-electrode setup under galvanostatic conditions. All components are commercially and readily available. The method is very easy to conduct and applicable to a variety of nitrile substrates, leading exclusively to primary amine products in yields of up to 89% using an easy work-up protocol.

Towards a General Access to 1-Azaspirocyclic Systems via Photoinduced, Reductive Decarboxylative Radical Cyclizations.

A convenient and versatile approach to important 1-azaspirocyclic systems relevant to medicinal chemistry and natural products is reported herein. The main strategy relies on a reductive decarboxylative cyclization of redox-active esters which can be rapidly assembled from abundant cyclic azaacids and tailored acceptor sidechains, with a focus on alkyne acceptors enabling the generation of useful exo-alkene moieties. Diastereoconvergent variants were studied and could be achieved either through remote stereocontrol or conformational restriction in bicyclic carbamate substrates.

C(sp)-H Ritter amination by excitation of generated iodine(III)-BF complexes.

Visible light excitation of iodine(III)-BF complex enables the formation of carbocations from C(sp)-H bonds. The complexes are generated catalytically from iodoarene, carboxylate ligand, the oxidizing agent Selectfluor, and the Lewis acid BF. This modular catalytic system allows the formation of synthetically valuable amine derivatives without a metal- or photocatalyst.

Synthesis of Unnatural α-Amino Acid Derivatives via Photoredox Activation of Inert C(sp)-H Bonds.

The synthesis of unnatural, tertiary amino acids is a challenging task. While decarboxylation-radical addition has been an important strategy for their formation, the use of alkyl radicals from C(sp)-H bonds has not been fully explored. Herein, we report a photocatalytic protocol for the synthesis of unnatural α-amino esters employing abundant alkanes and imines retaining full atom economy.