Visualization of the Mechanical Wave Effect on Liquid Microphases and Its Application for the Tuning of Dissipative Soft Microreactors

Kashin A. S., Degtyareva E. S., Ananikov V. P., J. Am. Chem. Soc. Au, 2021, ASAP.
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The development of approaches for creation of adaptive and stimuli-responsive chemical systems is particularly important for chemistry, materials science, and biotechnology. The understanding of response mechanisms for various external forces is highly demanded for the rational design of task-specific systems. Here, we report direct liquid-phase scanning electron microscopy (SEM) observations of the high frequency sound-wave-driven restructuring of liquid media on the microlevel, leading to switching of its chemical behavior. We show that under the action of ultrasound, the microstructured ionic liquid/water mixture undergoes rearrangement resulting in formation of separated phases with specific compositions and reactivities. The observed effect was successfully utilized for creation of dissipative soft microreactors formed in ionic liquid/water media during the sonication-driven water transfer. The performance of the microreactors was demonstrated using the example of controlled synthesis of small and uniform gold and palladium nanoparticles. The microsonication stage, designed and used in the present study, opened unique opportunities for direct sonochemical studies with the use of electron microscopy.

Catalytic C‐H Functionalization of Unreactive Furan Cores in the Bio‐derived Platform Chemicals

Karlinskii B.Ya., Ananikov V.P., Chem. Sus. Chem, 2021, ASAP.
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C‐H functionalization is one of the most convenient and powerful tools in the arsenal of modern chemistry, deservedly nominated as the "Holy Grail" of organic synthesis. A frequent disadvantage of this method is the need for harsh reaction conditions to carry out transformations of inert C‐H bonds, which limits the possibility of its use for modifying less stable substrates. Biomass‐derived furan platform chemicals, which have a relatively unstable aromatic furan core and highly reactive side chain substituents, are extremely promising and valuable organic molecules that are currently widely used in a variety of research and industrial fields. The high sensitivity of furan derivatives to acids, strong oxidants, and high temperatures significantly limits the use of classical methods of C‐H functionalization for their modification. New methods of catalytic functionalization of non‐reactive furan cores are urgently required to obtain a new generation of materials with controlled properties and potentially bioactive substances.

Comparative Study of Aryl Halides in Pd-Mediated Reactions: Key Factors Beyond the Oxidative Addition Step

Galushko A.S., Prima D.O., Burykina J.V., Ananikov V.P., Ignore. Chem. Front., 2021, ASAP.
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Although practical catalytic transformations involving aryl chlorides are difficult to implement, they are highly desirable since the starting compounds are inexpensive and readily available. Retarded oxidative addition of aryl chlorides to palladium catalyst as compared to aryl bromides and aryl iodides is typically taken for granted as an explanation for the overall inefficiency of the process. The comparative experimental study and analysis reported herein suggest that oxidative addition cannot be considered the sole reason of the observed low reactivity of aryl chlorides. Other factors were found to play an important role in influencing the reactivity of aryl halides. The present findings suggest that a substantial revision of catalyst design principles is necessary for successful transformations of aryl chlorides.