Application of NMR techniques to the determination of the composition of tobacco, coffee, and tea products

The application of NMR spectroscopy, including its up-to-date versions (correlation homo- and heteronuclear spectroscopy, Overhauser effect, solid-state NMR, etc.), to the analysis of tobacco and tobacco products, tea, and coffee is considered. The advantages and limitations of NMR techniques in the analysis of complex mixtures, as compared with chromatography-mass spectrometry and other instrumental techniques, are discussed based on particular examples.     

Synthesis, structural and spectral features of CH-Acids: Amides of 2,4-dinitrophenylcyanoacetic acid and their ammonium salts

New N-methylmorpholinium and triethylammonium salts of 2,4-dinitrophenylcyanoacetic acid were obtained. Their electronic and spatial structure was studied by IR, NMR spectroscopy (including two-dimensional correlation spectra HMQC and HMBC), as well as by XRD analysis.     

Synthesis of siloxane analogs of calixarenes

First siloxane analogs of calixarenes were synthesized based on the stereoregular cis-tetraphenylcyclotetrasiloxanetetrol. Different methods were used to study properties of new compounds in bulk, as well as their behavior at the water–air interface.     

Coupling of methylene-active compounds through a methylene bridge by the action of bis(dimethylamino)methane 1. Synthesis of 2,4-bis(diphenylphosphoryl)glutaronitrile

The reaction of diphenylphosphorylacetonitrile with bis(dimethylamino)methane gave 2,4-bis(diphenylphosphoryl)glutaronitrile. Its rac form was obtained by the synthesis followed by crystallization. However, the reaction of the latter with bases or acids in solution yielded the meso diastereomer.     

Synthesis of new multiblock copolymers via cross-metathesis reaction of polytrimethylsilylnorbornene and polycyclooctene

The cross-metathesis reaction between polytrimethylsilylnorbornene and polycyclooctene is investigated for the first time. Using the Grubbs Ru-carbene complex of the first generation, the synthesis of random multiblock copolymers of trimethylsilylnorbornene and cyclooctene is carried out. The effect of the reaction conditions on the block length and thermal and crystalline properties of new copolymers is studied by NMR, GPC, and DSC methods. With the use of in situ ¹Н NMR spectroscopy, the kinetics of the crossmetathesis reaction is investigated. As for unsubstituted polynorbornene (Polym. Sci., Ser. B 58, 292 (2016)), the catalyst interacts initially with polycyclooctene, giving a polymer carbene complex [Ru]=PCO. Further, this complex attacks the polytrimethylsilylnorbornene chain via cross reaction with formation of complex [Ru]=PNB-Si and a diblock copolymer of trimethylsilylnorbornene and cyclooctene as reaction products. The subsequent cross reactions form a multiblock copolymer with gradually increasing block length. Throughout the entire process, the concentration of [Ru]=PCO exceeds the concentration of [Ru]=PNB-Si by more than two orders of magnitude. Simultaneously, the total concentration of carbene complexes decreases in time through their decay. The reaction kinetics is satisfactorily described by a model proposed previously for interaction between polycyclooctene and polynorbornene.     

New magnetic nanomaterials based on ferrocene-containing polymers synthesized under ultrasonic irradiation

Russian Chemical Bulletin - A new magnetic nanomaterial was obtained based on soluble ferrocene-containing poly-phenylene synthesized under ultrasonic irradiation at room temperature. The maximum...     

Direct Heteroarylation versus Stille Polycondensation Reaction for the Synthesis of TQ1 Conjugated Polymer

We report a facile synthesis of the well‐known and highly promising conjugated polymer TQ1 using eco‐friendly direct heteroarylation reaction. Optimization of the reaction conditions yielded the target polymer with good optoelectronic and charge‐transport characteristics. The TQ1 polymer obtained in the direct heteroarylation reaction delivered power conversion efficiency of ～5% in organic bulk heterojunction solar cells, which matches well the characteristics of the reference devices assembled using TQ1 batch synthesized via conventional Stille polycondensation reaction. The obtained results highlight the potential of the direct heteroarylation reaction as an efficient and environment‐friendly alternative to Stille cross‐coupling in the design of high‐quality semiconductor materials for organic electronics. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 776–782     

Rotation of the polarization plane of waves in anisotropic media

Conditions under which rotation of the wave polarization plane is observed are formulated for anisotropic media with various symmetry types. The results may be of interest in solution of the inverse problem of constructing model geophysical media from an observed polarization plane rotation effect. Institute of Planetary Geophysics, Russian Academy of Sciences: Moscow Institute of Radioengineering, Electronics and Automation (Technical University); Moscow Academy of Instrumentation and Informatics. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 82–89, May, 1996.     

Temperature dependence of a gluon condensate in a model with a spherically symmetric non-Abelian field

The single-loop approximation is used to calculate a gluon condensate in an external spherically symmetric non-Abelian chromomagnetic field. Moscow Institute of Radio Engineering, Electronics, and Automation. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 18–22, July, 1997.