Synthesis, electrochemistry and structural characterization of new dimeric cobalt η2-alkyne carbonyl complexes

Catalytic Deprotection of Alkyne Dicobalt Hexacarbonyl Complexes using Near-Infrared Photocatalysis

Dicobalt hexacarbonyl complexes are well-known for their applications in the Nicholas reaction or simply as a protecting group for alkynes. To recover the alkyne, demetalation is necessary, which usually involves a stoichiometric amount of an oxidizing agent or a strong ligand. This article reports a demetalation methodology based on a photocatalytic process. This approach employs a photocatalyst under aerobic conditions, and the optimal results were achieved using mild near-infrared irradiation. A mechanistic investigation is also presented to elucidate how the photocatalytic system promotes this deprotection. This tool is compatible with the one-pot reaction and orthogonal deprotection of alkynes, offering new perspectives for further applications.

Controllable preparation of magnetic carbon nanocomposites by pyrolysis of organometallic precursors, similar molecular structure but very different morphology, composition and properties

Organometallic compounds were synthesized for solid-state pyrolysis to research the structure–property relationship between the precursors and the as-generated magnetic carbon nanocomposites.

En route to dinitroacetylene: nitro(trimethylsilyl)acetylene and nitroacetylene harnessed by dicobalt hexacarbonyl

Dinitroacetylene and other nitroacetylenes are attractive stoichiometric precursors to high energy-density materials, but suffer from high reactivity and thermal instability. Herein, we report that nitroacetylenes can be dramatically stabilized in the form of their dicobalt hexacarbonyl complexes. In particular, we describe the syntheses and characterization of the first two transition-metal complexes of nitroalkynes, [μ-1-nitro-2-(trimethylsilyl)ethyne-1,2-diyl]bis(tricarbonylcobalt)(Co-Co) and [μ-1-nitroethyne-1,2-diyl]bis(tricarbonylcobalt)(Co-Co). The chemistry of these compounds reveals their potential as reaction partners in [2+2+2] cyclotrimerizations, furnishing nitroindane, nitrotetralin, and trinitrobenzene products. The X-ray crystal structure of 1,3,5-trinitro-2,4,6-tris(trimethylsilyl)benzene presents a distorted, yet planar, aromatic ring.