MgFe2O4 nanoparticle ferrites were synthesized by combustion technique using pure ferric nitrate and magnesium nitratecarbonate. The magnetically separable MgFe2O4 MNP’s were found to be hyper active catalyst for the synthesis of a wide range of biologically active five and six-membered heterocyclic moieties at refluxing conditions. Reaction times are lowest in comparison to all reported in literature with excellent yields. Strong electron pull of Fe3+ is responsible for its hyper activity, which has been substantiated by substitution of Fe3+ by other trivalent metal ions.
The synthesis of new hybrids 1,3,4-oxadiazol-2-thione with acridine 9(10H)-one is carried out. Their structure is confirmed by LC-MS, IR-, 1H and 13C NMR-spectroscopy. The thione-thiol equilibrium was investigated in eight solvents with different relative permittivity with the help of UV-spectroscopy and quantum chemistry methods using DFT/B3LYP and HF bases. The results of the experimental calculations are in agreement with theoretical ones and have shown the prevalence of the thione.
Reactions of nucleophilic substitution between 5-R-2,3-dichloro-1,4-naphthoquinones and 4-amino-5- heteryl-4H-1,2,4-triazoles-3-thiols were carried out. It is shown that the interaction can take place in two alternative ways and the reaction direction is controlled by reaction conditions. Search of differences in atoms reactivity in investigated molecules by comparing the calculated Fukui atonic indices was conducted.
The reaction of azo-bis-cyanuric chloride as strong electrophilic aza-dienophile in Diels-Alder cycloaddition with a number of dienes of different nucleophilicity, namely 2,3-dimethylbutadiene, 2-methylbutadiene and 1-acethoxybutadiene, was carried out and computationally analyzed on B3LYP/6-31G(d,p) level. Local and global reactivity indices, based on FMO theory, as well as TS geometries and activation energies were calculated. Reaction proceeds rapidly with high yields and in mild conditions. Ways of products further modification by chlorine atoms substitution were also studied.
The most urgent task of organic and pharmaceutical chemistry today is the search for new biologically active compounds, which in future can be used as promising substances for the development of new low-toxic, high-performance medicinal products. To this end, heterocyclic N-derivatives of 1,4-dichloroanotoquinone were synthesized and their drug-like characteristics were determined.
The nucleophilicity of the amino group in the 6-th and 7-th positions of 1,4-naphthoquinone and the comparison with the activity of the amino group in the 2-nd position of 1,4-naphthoquinone have been investigated. Therefore, alkylation reactions were performed with alkyl iodides, acylation with acetate anhydride, and also interaction with sulfinyl chloride and sulfonyl chloride was carried out.
This paper describes the use of 1,4-naphthoquinones, as the sentimental equivalents of
electron-diphosphate alkenes, as activation by dipolarophyll in the reaction [3+2] cyclization.
The paper finds that the use of a silver acetate catalyst strictly spatially coordinates a molecule
of azometinilide in a transitional state, which explains the production of exclusively ciscoupling
products. In the analysis of the optimization of the reaction conditions, the following
regularity was established: during the course of the reaction according to the classical
The Diels-Alder reaction is widely used in organic synthesis, since it allows using a variety of dienes and dienophiles to obatin six-membered cycles in one step. Azo compounds, especially with electron deficient substituents, such as the 1,3,5-triazine ring, can interact as active dienophiles in the Diels-Alder reactions.
В результаті взаємодії азо-біс-ціанурхлориду зі стиролом був виділений один з ізомерів інвертованої реакції Дільса-Альдера з високим виходом. Для пояснення селективності реакції були проведені термодинамічні розрахунки на M06-2X/6-31G(d,p) рівні. Протікання реакції досліджувалось по трьох шляхах – з утворенням продукту нормальної ДА та двох регіоізомерів інвертованої ДА реакції.
A convenient method of synthesis of 2-amino-4,9-dioxo-4,9-dyhidronaphto[2,3-b] thiophene-3-carboxylic acid by interaction of 2,3-dichloro-1,4-naphthoquinone with ethylcyanacetate and sulfide sodium in ethanol was developed.The influence of different factors was investigated and probable mechanism of reaction proposed. Розроблено зручний метод синтезу 2-аміно-4,9-діоксо-4,9-дигідронафто[2,3-b] тіофен-3-карбонової кислоти на основі взаємодії 2,3-дихлоро-1,4-нафтохінону з етилціаноацетатом та сульфідом натрію в етанолі.