Atroposelective Chan-Evans-Lam Amination.

The synthetic control of atropoisomerism along C-N bonds is a major challenge, and methods that allow C-N atroposelective bond formation are rare. This is a problem because each atropoisomer can feature starkly differentiated biological properties. Yet, among the three most practical and applicable classical amination methods available: 1) the Cu-catalyzed Ullmann-Goldberg reaction, 2) the Pd-catalyzed Buchwald-Hartwig reaction, and 3) the Cu-catalyzed Chan-Evans-Lam reaction, none has truly been rendered atroposelective at the newly formed C-N bond.

Atroposelective Nenitzescu Indole Synthesis.

Invited for the cover of this issue is the group of Frederic W. Patureau at the RWTH Aachen University. The image depicts atropoisomerism, in particular through the helix-shaped vines in the forefront focus.

Atroposelective Nenitzescu Indole Synthesis.

In the past decade, compounds bearing a stereogenic C-N axis have gained significant attention in fields ranging from ligand to drug design. Yet, the atroposelective synthesis of these molecules remains a considerable challenge. In contrast to recent methods using more advanced chiral catalysts, a very simply accessed Jacobsen-type chromium(III)-salen complex was used here as a chiral enantiopure Lewis acid catalyst for a highly atroposelective Nenitzescu indole synthesis.

TEMPO-mediated late stage photochemical hydroxylation of biaryl sulfonium salts.

The late stage photochemical hydroxylation of biaryl sulfonium salts was enabled with a TEMPO derivative as a simple oxygen source, in metal free conditions. The scope and mechanism of this exceptionally simple synthetic method, which constructs important arylated phenols from aromatic C-H bonds, are herein discussed.

Phosphine-Catalyzed Dearomative [3 + 2] Cycloaddition of Benzoxazoles with a Cyclopropenone.

The triphenylphosphine-catalyzed dearomative [3 + 2] cycloaddition of benzoxazoles with 1,2-diphenylcyclopropenone is herein described. The reaction scope, mechanism, and possible future applications of this rare organocatalyzed cycloaddition are herein discussed.

Dehydrogenative C-H Phenochalcogenazination.

Heavy-atom-modified chalcogen-fused triarylamine organic materials are becoming increasingly important in the photochemical sciences. In this context, the general and direct dehydrogenative C-H phenochalcogenazination of phenols with the heavier chalcogens selenium and tellurium is herein described. The latter dehydrogenative C-N bond-forming processes operate under simple reaction conditions with highly sustainable O serving as the terminal oxidant.