Cobalt Catalyzed α-Hydroxylation of Arylacetic Acid Equivalents with Dioxygen.

A cobalt catalyst, under oxidative conditions, facilitates the single electron transfer process in -pyridyl arylacetamides to form α-carbon-centered radicals that readily react with molecular oxygen, giving access to mandelic acid derivatives. In contrast to the known benzylic hydroxylation approaches, this approach enables chemo- and regioselective hydroxylation at a benzylic position adjacent to (-pyridyl)amides. Mild conditions, broad scope, excellent selectivity, and wide synthetic practicality set up the merit of the reaction.

Base-Promoted Tandem Pathway for Keto-Amides: Visible Light-Mediated Room-Temperature Amidation Using Molecular Oxygen as an Oxidant.

Herein, we report metal- and photocatalyst-free room-temperature amidation for α-ketoamide synthesis from feedstock phenacyl bromides and amines using molecular oxygen as an oxidant as well as a source of oxygen in the amide segment. Visible light-mediated base-promoted one-pot sequential C-N/C═N/C═O bond formation takes place in a tandem manner to afford the desired product. Functional group tolerance (benzylic alcohol, keto, cyano, nitro, halo, etc.

Visible light photocatalysts from low-grade iron ore: the environmentally benign production of magnetite/carbon (FeO/C) nanocomposites.

Magnetite (FeO) nanoparticles coated with dextrose and gluconic acid possessing both super-paramagnetism and excellent optical properties have been productively synthesized through a straightforward, efficient and cost-efficient hydrothermal reduction route using Fe as sole metal precursor acquired from accumulated iron ore tailings-a mining waste that usually represents a major environmental threat. FeO/C nanocomposites were fully elucidated by FEGSEM and TEM, revealing a combination of platelets (<1 μm) capped by particles (<10 nm) and magnetite which was verified by XPS, which demonstrated also oxygen deficiency. A dextrose/gluconic acid coating was elucidated by Fourier transform-infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA).