Comparison of Plasma Deposition of Carbon Nanomaterials Using Various Polymer Materials as a Carbon Atom Source

Carbon nanowalls are promising materials for various electrochemical devices due to their chemical inertness, desirable electrical conductivity, and excellent surface-to-mass ratio. Standard techniques, often based on plasma-assisted deposition using gaseous precursors, enable the synthesis of top-quality carbon nanowalls, but require long deposition times which represents a serious obstacle for mass applications. Here, an alternative deposition technique is presented. The carbon nanowalls were synthesized on titanium substrates using various polymers as solid precursors. A solid precursor and the substrate were mounted into a low-pressure plasma reactor. Plasma was sustained by an inductively coupled radiofrequency discharge in the H-mode at the power of 500 W. Spontaneous growth of carbon nanomaterials was observed for a variety of polymer precursors. The best quality of carbon nanowalls was obtained using aliphatic polyolefins. The highest growth rate of a thin film of carbon nanowalls of about 200 nm/s was observed. The results were explained by different degradation mechanisms of polymers upon plasma treatment and the surface kinetics.

Visible-light-mediated catalyst-free synthesis of unnatural α-amino acids and peptide macrocycles

The visible light induced, photocatalysts or photoabsorbing EDA complexes mediated cleavage of pyridinium C-N bond were reported in the past years. Here, we report an ionic compound promote homolytic cleavage of pyridinium C-N bond by exploiting the photonic energy from visible light. This finding is successfully applied in deaminative hydroalkylation of a series of alkenes including naturally occurring dehydroalanine, which provides an efficient way to prepare β-alkyl substituted unnatural amino acids under mild and photocatalyst-free conditions. Importantly, by using this protocol, the deaminative cyclization of peptide backbone N-terminals is realized. Furthermore, the use of Et3N or PPh3 as reductants and H2O as hydrogen atom source is a practical advantage. We anticipate that our protocol will be useful in peptide synthesis and modern peptide drug discovery.

Copper(I)-catalysed site-selective C(sp3)–H bond chlorination of ketones, (E)-enones and alkylbenzenes by dichloramine-T

Strategies that enable intermolecular site-selective C–H bond functionalisation of organic molecules provide one of the cornerstones of modern chemical synthesis. In chloroalkane synthesis, such methods for intermolecular site-selective aliphatic C–H bond chlorination have, however, remained conspicuously rare. Here, we present a copper(I)-catalysed synthetic method for the efficient site-selective C(sp3)–H bond chlorination of ketones, (E)-enones and alkylbenzenes by dichloramine-T at room temperature. A key feature of the broad substrate scope is tolerance to unsaturation, which would normally pose an immense challenge in chemoselective aliphatic C–H bond functionalisation. By unlocking dichloramine-T’s potential as a chlorine radical atom source, the product site-selectivities achieved are among the most selective in alkane functionalisation and should find widespread utility in chemical synthesis. This is exemplified by the late-stage site-selective modification of a number of natural products and bioactive compounds, and gram-scale preparation and formal synthesis of two drug molecules.

Decomposition CO₂ and CO in Flow of Gases by Means of Technical Ferrogravitational Field

The author's experimental studies shown that magnetic poles (magnetic charges) are real structural components of atoms and substance. It is the magnetic poles, and not the electrons moving are direct sources of all magnetic fields in nature. The main reasons for ignoring magnetic charges in physical science are the hard conditions for their confinement in the structures of substance which is fundamentally different from the confinement of electrons, as well as the vicious electric magnetism of Maxwell (1873). True magnetic poles have been “buried alive” in physical theory under such theoretical surrogates as the magnetic moments of electrons. The electromagnetic shells of atoms composed of electric and magnetic charges are the sources of gravitational field which is the vortex electromagnetic field and is described by vortex vector rot[E – H]. Depending on the state of vortex vectors rot[E – H] in the composition of gravitational fields (GF) emitted by atoms, these fields are subdivided into paragravitational (PGF) and ferrogravitational (FGF). The sources of ferrogravitational field are repelled from sources of paragravitational field, for example, from Earth. The forces of such repulsion depend on the degree ferropolarization of gravitational field of atom - source of FGF, and the physical manifestation such repulsion is еthe effect of the ferrogravitational levitation (FGL), which discovered and investigated by the author. The FGL effect is also realized between the atoms emitting PGF and FGF in the formulations of chemical compounds. When an external FGF acts on CO2 molecule the process ferropolarization of gravitational field of oxygen atom is realized, which should be defined as the gravito-plastic source. In this case, the carbon atom, which is the gravito-stable mass, remains of paragravitational. At interatomic distances <1 Å the forces of the gravito-levitation repulsion may be very significant and lead to the rupture of chemical bonds between oxygen and carbon atoms and to the disintegration of the molecule CO2. It is highly probable that the process of decomposition of CO2, similar to that described above, is carried out in the cells of leaves of green plants, which emit precisely the ferrogravitational field. The decomposition of CO2 by FGF and the supply of oxygen to green plants is natural process that takes place in leaf cells called photosynthesis. However, photons in this process are only a stimulating factor contributing to the ferropolarization of gravitational field emitted by atoms oxygen in the composition of green plant cells.