Synthesis and structure of new chlorine containing calix[4]resorcinols

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Rearrangement in the systems ethyl bromopyruvate-1-(cyclohex-1-enyl)piperidine, -pyrrolidine,and -morpholine as an effi cient approach to 4,5,6,7-tetrahydroindoles

Russian Chemical Bulletin - 1-(Cyclohex-1-enyl)piperidine, -pyrrolidine, and -morpholine react with ethyl bromopyruvate in refluxing dioxane to afford the corresponding 4,5,6,7-tetrahydroindole...     

Influence of amidoammonium calix[4]resorcinarenes on methyl orange protolytic equilibrium: supramolecular indicator systems

Here, we report on the study of cationic amidoammonium calix[4]resorcinarenes 1–5 of various lipophilicity capable of binding acid–base indicator methyl orange (MO). We identified the contributions of macrocycle aggregation and conformational mobility in the binding of MO. The effective pK_a values of bound MO systematically decrease as the size and the packing density of the aggregates increase with an increase in calixresorcinarene lipophilicity. Consideration of a series of macrocycles clearly shows that large aggregates form most stable complexes, binding guests not on individual level but as aggregates. It was found that the most stable MO complex with 5 is formed due to electrostatic binding with ammonium groups of the macrocycle and incapsulation of MO in a hydrophobic layer of the aggregates. We have shown that competitive binding of MO and cationic surfactants by aggregates of 5 is suitable for visual/spectrophotometric detection of colourless anionic substrates.     

α-Amino acetals containing a phosphonate or phosphine oxide group. Synthesis and reactions with resorcinols

New α-amino acetals containing a phosphonate or phosphine oxide group were synthesized by the Kabachnik-Fields reaction in the ternary system amino acetal-paraformaldehyde-dialkyl phosphonate (or dialkylphosphine oxide). Condensation of dialkyl (2,2-dimethoxyethylamino)methylphosphonates with resorcinol and its derivatives in ethanol in the presence of hydrochloric acid, apart from the corresponding 2,2-bis(polyhydroxyphenyl) ethylammonium salts, gave 2,5-bis(polyhydroxyphenyl)-1,4-bis[(dialkoxyphosphoryl)methyl]-piperazines. Dialkyl[(2,2-dimethoxyethylamino)methyl]phosphine oxides (Alk = C₈H₁₇, C₁₀H₂₁) did not react with resorcinol derivatives under similar conditions, and analogous ammonium salts were obtained by heating the reactants in boiling trifluoroacetic acid.     

Synthesis of 3,5-di-tert-butyl-4-hydroxyphenylsulfanylmethyl-substituted tetramethylcalix[4]resorcinarenes

Russian Journal of Organic Chemistry -     

Unusual Reaction of Tetramethylcalix[4]resorcinolarene with 3,5-Di-tert-butyl-4-hydroxybenzyl Acetate

Russian Journal of General Chemistry -     

Isatin acylhydrazones with sterically hindered phenolic fragments: synthesis and structures

Isatin acylhydrazones with sterically hindered phenolic fragments were obtained. Their structures were determined using 1D and 2D 1H and 13C NMR spectroscopy and X-ray diffraction. The products synthesized by condensation of isatin and 1-(3,5-di- tert-butyl-4-hydroxybenzyl)-l H-indole-2,3-dione with 3-(3,5-di- tert-butyl-4-hydroxyphenyl)propiono-hydrazide exist as E- and Z-isomers about the C=N bond. E— Z isomerization takes place in boiling ethanol. The E-isomer of the condensation product from isatin and 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionohydrazide was structurally characterized using X-ray diffraction: this isomer is a cis-conformer about the amide group and has a E-configuration about the N—N bond. According to data on the concentration dependence of the signals for the NH protons in the 1H NMR spectra, the acylhydrazones obtained are stabilized in solution by intra-and intermolecular hydrogen bonding.