Steric structure of quaternary ammonium salts of the 3-[alkyl(aryl)amino]-1-[alkyl(aryl)iminio]-1H-isoindole series was studied by 1 H NMR spectroscopy and X-ray analysis. The examined salts are characterized by E,E configuration of substituents with respect to the exocyclic C-N bonds, and the presence of ortho-and meta-substituents in the benzene rings on the nitrogen atoms gives rise to atropisomers. Sterically hindered N- (2,4,6-trimethylphenyl) derivative was found to exist as Z,Z isomer which undergoes irreversible thermal isomerization into the more stable E,E isomer through intermediate Z,E structure. The reactions of 1,1,3-trichloro-1H-isoindole with secondary aromatic amines having an electron-withdrawing substituent in the ortho position in the presence of organic bases (triethylamine, N,N-dimethylbenzylamine) are accompanied by decomposition of the latter and formation of unsymmetrically substituted salts of the 3-[alkyl(aryl)amino]-1-(dialkyliminio)-1H-isoindole series, which contain both arylamine residue and dialkylamino group and are also characterized by atropisomerism.Compounds of the aminoimino-1H-isoindole series can exist as different tautomers and geometric isomers [1]. The latter appear due to the presence of double exocyclic C=N bonds. For instance, 1,3-bis(arylimino)-2,3-dihydro-1H-isoindoles generally exist as mixtures of tautomers, as well as of Z,E isomers [2]. Their NMR spectra contain two sets of signals corresponding to Z,E and Z,Z isomers. By contrast, quaternary isoindolium salts of the 3-amino-1-iminio-1H-isoindole series are stable as E,E isomers of 1,3-bis-[alkyl(aryl)amino] derivatives and Z,Z isomers of the salts derived from cyclic fatty-aromatic amines [3].3-Amino-1-iminio-1H-isoindole salts cannot be synthesized by direct alkylation of the corresponding bases, 1,3-bis(arylimino)-2,3-dihydro-1H-isoindoles; however, such salts are readily available via nucleophilic replacement of chlorine in 1,1,3-trichloro-1H-isoindole (I) by secondary amine residues in the presence of excess amine [3]. With a view to examine the effect of steric factors on the state of equilibrium between stereoisomers we synthesized 1,3-bis(arylamino)isoindolium salts having ortho substituents in the aromatic ring. The reaction readily occurred in anhydrous aprotic solvent, such as chloroform, aceto-

ChemInform Abstract Simultaneous reaction of 1,1,3-trichloro-1H-isoindole (II) with the anilines (I) and an excess of the tertiary amines (III) or (V) leads predominantly to the formation of the dialkylaminoaryliminoisoindoles (IV) or (VI). The diiminodihydroisoindole (VIIb) is prepared from (II) and excess (Ib).

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Це дослідження є складовою частиною науково-дослідної теми «Морфофункціональний моніторинг стану органів і систем організму за умов порушення гомеостазу» (номер державної реєстрації 0115U000685). Реферат. Метою дослідження є вивчення кристалохімічних характеристик біологічно значимих апатитів кальцію на прикладі губчастої кісткової тканини для виявлення та дослідження біологічних ефектів структурних недосконалостей та мобільних іонних компонентів поверхневої локалізації при фізіологічній мінералізації.

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