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An efficient copper(I)-catalyzed direct regioselective arylamination of various heterocyclic N-oxides was achieved successfully under redox-neutral conditions using anthranils as arylaminating reagents. The developed protocol is simple, straightforward, and economic with a broad range substrate scope. The dual functional groups in the final molecules were utilized to construct structurally and functionally diverse nitrogen-containing organic π-conjugated systems.

Tetrahydrothiophenes and tetrahydrothiopyrans are an important class of compounds both from synthetic and biological points of view and have attracted the attention of many synthetic chemists and biologists over the years. Their high synthetic utility and diverse distribution in nature have made tetrahydrothiophenes and tetrahydrothiopyrans privileged motifs in organic chemistry. The last decade has witnessed great exploration of organocatalytic domino methods for the synthesis of enantiopure tetrahydrothiophenes and tetrahydrothiopyrans containing multiple stereocentres. The application of new bidentate reagents containing sulfur moieties in the development of double Michael reactions has revolutionized their synthesis. This microreview highlights recent organocatalytic asymmetric approaches to the synthesis of tetrahydrothiophenes and tetrahydrothiopyrans and describes the advances that have been made over the years.

Phenoxazines, in particular N-arylated phenoxazines, represent an increasingly important scaffold in the material sciences. Moreover, the oxygen-gas-mediated dehydrogenative phenochalcogenazination concept of phenols has been developed and exemplified for X = sulfur and recently for X = selenium and tellurium. The smallest chalcogen, X = oxygen, is herein exemplified with various functional groups under a likewise trivial oxygen atmosphere.

The titanium complex of the cis‐1,2‐diaminocyclohexane (cis‐DACH) derived Berkessel‐salalen ligand is a highly efficient and enantioselective catalyst for the asymmetric epoxidation of terminal olefins with hydrogen peroxide (“Berkessel‐Katsuki catalyst”). We herein report that this epoxidation catalyst also effects the highly enantioselective hydroxylation of benzylic C−H bonds with hydrogen peroxide. Mechanism‐based ligand optimization identified a novel nitro‐salalen Ti‐catalyst of the highest efficiency ever reported for asymmetric catalytic benzylic hydroxylation, with enantioselectivities of up to 98 % ee, while overoxidation to ketone is marginal. The novel nitro‐salalen Ti‐catalyst also shows enhanced epoxidation efficiency, as evidenced by e.g. the conversion of 1‐decene to its epoxide in 90 % yield with 94 % ee, at a catalyst loading of 0.1 mol‐% only.