Yu. N. Biglova

New monomers for fullerene-containing polymers

By reaction of 2-(acryloyloxyethyl) and (undecen-10-en-1-yl) methylmalonates with fullerene C60 in the system toluene-CBr4-DBU, and also by reaction of 2-(2,2-dichloroacetoxy)ethyl acrylate with C60 in the system toluene-DBU the corresponding products of fullerene monocyclopropanation were synthesized.

Solar-energy photoconverters based on thin films of organic materials

Novel developmental prototypes of solar cells based on binary donor-acceptor systems in the form of a combination of polyaniline derivatives with fullerene-containing polymers were obtained. Current-voltage characteristics of solar cells were measured, and numerical values of parameters, including open-circuit voltage, short-circuit current, filling factor, and coefficient of efficiency, were calculated on their basis.

UV spectroscopy of monosubstituted derivatives of 1,2-dihydro-C60-fullerenes

UV spectroscopy is used to determine the molar absorption coefficients of C60 fullerene and monosubstituted 1,2-dihydro-C60-fullerenes in different solvents. It is found that the extinction coefficient of C60 at 330 nm (the main absorption band most frequently used for qualitative and quantitative determination of the C60 content) is independent of the nature of the solvent and is ∼54400 M−1·cm−1. The molar absorption coefficients of a series of monosubstituted 1,2-dihydro-C60-fullerenes are practically independent of the chemical structure and the length of the substituent and are 35700 M−1·cm−1 (λ ∼ 328 nm) and 115250 M−1·cm−1 (λ ∼ 257 nm). It is shown that the substitution in fullerene proceeds via the double 6,6 bond, as evidenced by the absorption band at 424 nm in the spectra of these compounds, which is characteristic of monosubstituted methanofullerenes.

Ring-opening metathesis polymerization (ROMP) of fullerene-containing monomers in the presence of a first-generation Grubbs catalyst

New norbornene-type monomers containing covalently bound C60 fullerene have been obtained. In the presence of the 1st generation Grubbs catalyst [(PCy3)2Cl2RuCHPh] (Cy is cyclohexyl), these monomers smoothly undergo homopolymerization and copolymerization with parent fullerene-free monomers. The homopolymers are insoluble in common organic solvents, while the copolymers obtained at different molar ratios to their fullerene-free analogues are very soluble in organic solvents and can be suitable for the preparation of thin films.

Polynorbornenes modified by methanofullerene and 1-phenyltetrazol-5-ylsulfanylmethyl blocks

Ring-opening metathesis polymerization of norbornene monomers linked to fullerene and 1-phenyltetrazol-5-ylsulfanylmethyl fragments at a molar ratio of 1: 1 afforded a copolymer containing 30% of fullerene units and soluble in organic solvents.

UV spectroscopy of methanofullerene derivatives with different degrees of substitution

Compounds from the series of methanofullerenes with different degrees of functionalization were studied by UV spectroscopy. As the number of substituents increased, a hypsochromic shift of the characteristic absorption bands took place and the optical density of the solutions of the compounds at characteristic maxima decreased. A similar dependence was also noted for the ratio of the optical densities of the 258 and 329 nm bands typical for fullerene (A258/A329). An exponential dependence of the molar absorption coefficients of metanofullerenes on the degree of functionalization of the fullerene nucleus was found.

Preparation and investigation of soluble functionalized polyanilines

Soluble electron-donor conducting (co)polymers based on functionalized monomeric anilines have been synthesized and characterized for the first time. It has been shown that there is a good correlation between the results obtained from investigations of the electrochemical properties of polyaniline derivatives by the methods of cyclic voltammetry and on the basis of the temperature dependence of the electrical conductance. The polymer based on 2-(1-methyl-2-buten-1-yl)aniline has the lowest energy level of the highest occupied molecular orbital, which determines the prospects for its use as a donor in the active layer when designing organic solar cells.

Synthesis of chloramphenicol conjugate with fullerene C60

Main efforts in the design and synthesis of organofunctionalized derivatives of fullerene C60 for medical purposes are addressed to create water-soluble compounds [1–3]. Among them, antiviral [4], anticarcinogenic [5], and antibacterial agents [6], radical scavengers [7], etc. [8], have been found. An important research line in this field is the synthesis of coordination and covalently bound C60 compounds with biologically active molecules used in medical practice. For example, the anticancer activity of the C60‒doxorubicin complex is higher by a factor of 1.5‒2 than the activity of doxorubicin taken alone [9]; analogous effect is observed for the complex C60‒dexamethasone [10]. As a rule, the complexation improves transport and prolongs action of drugs, and in some cases synergistic effect is achieved. A different situation is observed with covalent bonding of C60 with drugs. Zakharian et al. [11] proposed to use C60 conjugate with paclitaxel (Taxol) for lipophilic chemotherapy of lung cancer. It was noted that C60 is an ideal partner for the lipophilization of drugs via conjugation. Conjugates of C60 with antibiotics [12] have been patented, and C60 conjugates with isoniazid [13], dehydroabietylamine [14], amino acids [15], and other biologically active molecules have been synthesized. In most cases, the biological activity profile was retained; however, it may change since a radically new molecular architecture is concerned.

UV spectroscopic quantitative determination of methanofullerene derivatives with a different degree of substitution

A spectroscopic method for the analysis of compounds belonging to methanofullerenes with different functionalization and a number of substituents is developed. In order to determine the composition of mixtures of these compounds the standard spectrophotometric procedure along with derivative spectroscopy are applied. Acceptable reproducubility and sensitivity of the methods used are demonstrated on model mixtures of fullerene derivatives. The reaction mass obtained in the interaction of fullerene with diallyl ester of malonic acid is analyzed.

Bingel Cycloaddition of N-Maleopimarimide-Substituted Amino-Acid Chloromethylketones to Fullerene C60

Lipophilic conjugates of fullerene C60 were prepared via Bingel [2+1]-cycloaddition of chloromethylketones based on N-maleopimarimide-substituted amino acids to the fullerene framework.