Nano-Structured Metal Chalcogenides as Reagents for the Catalytic Carbon–Sulfur Bond Formation in Cross-Coupling Reaction

Solid-State C-S Coupling in Nickel Organochalcogenide Frameworks as a Route to Hierarchical Structure Transfer to Binary Nanomaterials

In this work, the transfer of the flexible and easily tunable hierarchical structure of nickel organochalcogenides to different binary Ni-based nanomaterials via selective coupling of organic units was developed. We suggested the use of substituted aryl groups in organosulfur ligands (SAr) as traceless structure-inducing units to prepare nanostructured materials. At the first step, it was shown that the slight variation of the type of SAr units and synthetic procedures allowed us to obtain nickel thiolates [Ni(SAr)₂]_n with diverse morphologies after a self-assembly process in solution. This feature opened the way for the synthesis of different nanomaterials from a single type of precursor using the phenomenon of direct transfer of morphology. This study revealed that various nickel thiolates undergo selective C-S coupling under high-temperature conditions with the formation of highly demanding nanostructured NiS particles and corresponding diaryl sulfides. The in situ oxidation of the formed nickel sulfide in the case of reaction in an air atmosphere provided another type of valuable nanomaterial, nickel oxide. The high selectivity of the transformation allowed the preservation of the initial organochalcogenide morphologies in the resulting products.

Exploring the performance of nanostructured reagents with organic-group-defined morphology in cross-coupling reaction

The great impact of the nanoscale organization of reactive species on their performance in chemical transformations creates the possibility of fine-tuning of reaction parameters by modulating the nano-level properties. This methodology is extensively applied for the catalysts development whereas nanostructured reactants represent the practically unexplored area. Here we report the palladium- and copper-catalyzed cross-coupling reaction involving nano-structured nickel thiolate particles as reagents. On the basis of experimental findings we propose the cooperative effect of nano-level and molecular-level properties on their reactivity. The high degree of ordering, small particles size, and electron donating properties of the substituents favor the product formation. Reactant particles evolution in the reaction is visualized directly by dynamic liquid-phase electron microscopy including recording of video movies. Mechanism of the reaction in liquid phase is established using on-line mass spectrometry measurements. Together the findings provide new opportunities for organic chemical transformations design and for mechanistic studies.

Sulfides Synthesis: Nanocatalysts in C–S Cross-Coupling Reactions

The C–S cross-coupling reaction of aryl halides with thiols or sulfur sources is a key and valuable synthetic transformation in chemistry and medicine as well as in biology, and the development of novel efficient synthetic protocols for the synthesis of the corresponding products (sulfides) is highly desired. Among a wide range of catalysts used in C–S coupling reactions, metallic nanocatalysts have attracted notable interest. Herein, we summarize recent breakthroughs in the arena of metal nanocatalysts employed in C–S cross-coupling reactions with the goal of stimulating further progress in this field. This review is divided into three main sections according to the nature of the metal nanocatalysts discussed. The first section focuses on naked or purely metallic catalysts in nano-size, such as Cu, Pd, Ni, and In. The second section focuses on the role of Fe3O4 magnetic nanoparticles and mesoporous silica nanomaterials, such as MCM-41 and SBA-15, as catalyst supports. Finally, the third section focuses on the catalytic activities of copper ferrite nanoparticles in C–S cross-coupling reactions. Additionally, the recovery and reusability of the nanocatalyst, which are very important from commercial and economical points of view, are comprehensively discussed in this review.