The article is devoted to research of binary mixtures of fat acids by means of experimental and calculation methods
The article presents the results of the development of
an alternative model for calculating the values of
atomic radius. A formula was derived for calculating
the atomic radius of the elements of the Periodic
System of DI Mendeleev. The optimal calculation
conditions for the proposed model are found. It is
shown that the curve of the dependence of the value of
the correction coefficient x on the atomic number of
the element in form coincides with the dependence of
the ionization energy on the charge number
Correlations between experimental dipoles moments and values of the difference of first potentials ionization of atoms and molecules (ΔE) for three -coordinated molecules of types ÐÐ¥3 (Ð=N, P, As, Sb are carried out; X=F, Cl, Br, I ) are described.
Exponential functions of dependence μ= f(ΔE) for rows ÐF3 andÐCl3 are received. Within the valence of shell electron pair repulsion theory it is shown, that the molecular dipole moments can be divided to dipol moments of ions of separate atoms, which, naturally changing, are transferred in the ranks of molecules ÐÐ¥3
By the method of the dipole moments the connections of (p-XC6H4)3As=N-C6H4-Y series have been examined. The method of the vector-statistical analysis of the dipole moments helped to define the ranges and directions of the moments of (Сар)3As=N-Cар, (Сар)3As=N и N-Cар series. There has been shown that the substitution of the para-assistants X and Y in aromatic groups doesn't lead to an additional interaction influencing the electronic properties of the (Сар)3As=N-Cар group. The comparative analysis of the (Сар)3Ð=N-Cар (Ð=P, As) group moments specifies the essencial shift of the electron density to Сар(N) when replacing atom P to As
The present article belongs to the area of organic chemistry, namely, to chemistry of heterocyclic compounds. For the purpose of optimization of a method of synthesis the threecyclic heteroaromatic systems containing a pyridi-ne, thiophen and pyrimidine ring in one molecule, - tetrahydropyridothienopyrimidinon and dihydropyri-dothienopyrimidinon – reaction 3-aminothieno[2,3-b]-pyridine-2-carbokxamides with aromatic aldehydes is studied, some of which contain pharmacolodical groups. Reaction was carried out in the conditions of an acid catalysis – is used p-TsOH. Influence of the nature of solvent (toluene, ethanol, mix ethanol-dimethilform-amide (1:1)) on the course and the direction of reaction are studied. It is established that carrying out reaction in toluene leads to the dihydropyrimidine containing in situation 2 phenyl, 4-bromphenyl deputies. In the presence in a molecule of initial aldehyde of the deputy in orto-situation tetrahydropyrimidine are formed. Use of ethanol mainly leads to formation of a tetrahydro-pyrimidine ring. Boiling of initial substances in mix ethanol-DMF yields the results similar to use of toluene, but time of reaction is reduced twice. The way of receiving the dihydroderivatives short-term boiling of tetrahydropyrimidine is found in mix isopropanol-DMF (a volume ratio of solvents 1:3). Identity of the received substances is proved by method of a thin layer chroma-tography. The structure of the synthesized connections is confirmed with the element analysis. The structure of tertagidropirimidinon and digidropirimidinon is proved with use of data of IK and NMR 1H of the spectral analysis