Solid-state molecular oxygen activation using ball milling and a piezoelectric material for aerobic oxidation of thiols.

The agitation of BaTiO3 via ball milling converts mechanical energy into electrical energy, leading to the reduction of molecular oxygen via a single electron transfer pathway analogous to the photocatalytic reaction. This mechanoredox strategy for the oxidative coupling of thiols could eliminate waste and develop a recyclable methodology to accomplish organic transformations in a greener fashion, exhibiting promising potential for large-scale chemical manufacturing.

Scalable Synthetic Strategy for Unsymmetrical Trisubstituted s-Triazines.

A scalable synthetic strategy to produce a large variety of unsymmetrical trisubstituted 1,3,5-triazines was developed. This protocol applied in situ formed acyl isocyanate from amide to react with amidine, introducing two substituents to the 1,3,5-triazinone ring with a low production cost and a simple workup procedure. The scalability of this method was demonstrated by translating a small-scale procedure to a multi-kilogram-scale synthesis. Chlorination and a further coupling reaction with various nucleophiles could provide unsymmetrical trisubstituted 1,3,5-triazines bearing diverse functional groups.

Surfactant-Type Catalyst for Aerobic Oxidative Coupling of Hydrazine with Thiol in Water.

A series of PEG-functionalized nitrogen ligands were developed to conduct an aerobic oxidative cross-coupling reaction between alkyl- or aryl-hydrazines with thiols in water. This surfactant-type catalyst enables high efficiencies and selectivities, while tolerating a large variety of functional groups. The mother liquor is still catalytically active after five runs.