Dimethyl [(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadienylidene)-methyl]phosphonate in reactions with aliphatic diols

Russian Journal of General Chemistry -     

Effect of copper(I) on the conformation of the thiacalixarene platform in azide-alkyne cycloaddition

New lower-rim tetrasubstituted p-tert-butylthiacalix[4]arene derivatives bearing alkyl, propargyl, or triazole-containing substituents were synthesized. The structures of these compounds were determined by 1D and 2D NMR spectroscopy in solution and by X-ray diffraction in the solid phase. The copper-catalyzed azide-alkyne cycloaddition (CuAAC) of azides to a mixture of 1,3-alternate–partial cone stereoisomers of dipropargyl derivatives of thiacalix[4]arene affords triazole-containing products exclusively in the 1,3-alternate conformation.     

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.     

Electroswitchable binding of [Co(dipy)<Subscript>3</Subscript>]<Superscript>3+</Superscript> and [Fe(dipy)<Subscript>3</Subscript>]<Superscript>2+</Superscript><Emphasis Type="Italic">n</Emphasis>-sulfonato(thia)calix[4]arenas

The methods of cyclic voltammetry, electrolysis, and spectrophotometry were used to study electrochemical properties of (TCAS + Fe³⁺ + dipy), (CCAS + Fe³⁺ + dipy), and (CCAS + Fe³⁺ + [Co(dipy)₃]³⁺) triple systems (where TCAS is n-sulfonatothiacalix[4]arene, CCAS is tetracarboxylate n-sulfonatocalix[4]arene, and dipy = α,α′-dipyridyl) in an aqueous solution. One-electron reduction of Fe(III) in the (TCAS + Fe³⁺ + dipy) system at pH 2.5 results in electroswitching of iron ions from the lower TCAS ring to the upper ([Fe(dipy)₃]²⁺). Reverse electrochemical switching of the system is impossible due to mediator ([Fe(dipy)₃]^2+/3+) oxidation of TCAS. Reverse electroswitching of Fe(III) ions from unbound to bound state as ([Fe(dipy)₃]²⁺) with CCAS has been revealed in the system (CCAS + Fe³⁺ + dipy) (pH 1.7) upon single-electron transfer, whereas reversible electroswitching by the upper rim of CCAS from one complex ion ([Co(dipy)₃]³⁺) to another ([Fe(dipy)₃]²⁺) has been demonstrated in the system ([Co(dipy)₃]³⁺ + CCAS + Fe³⁺ upon double-electron transfer. In all systems, electric switching was accompanied by synchronous color switching.     

Reaction of salicylalkylenediimines with 2-chloro-4,5-diphenyl-1,3,2-dioxaphospholene

Russian Journal of General Chemistry -     

Synthesis and some properties of tetrakis-3,5-di-<Emphasis Type="Italic">tert</Emphasis>-butyl-4-hydroxybenzylated calix[4]resorcinols

A method for the synthesis of new calix[4]resorcinols tetra-3,5-di-tert-butyl-4-hydroxybenzyl derivatives is developed. Their interaction with methyldichlorophosphonate, dimethyldichlorosilane in the presence of a base leads to formation of organophosphorus-organosilicon cavitands. Acetylation of hydroxybenzylated calix[4]resorcinols with acetic anhydride leads to products of either incomplete or full acetylation depending on experimental conditions.     

Supramolecular systems based on poly(ethyleneimines) and calix[4]resorcinarenes with alkylphosphonate fragments. Aggregation and catalytic activity

Aggregation in poly(ethylenimine)-calix[4]resorcinarene-water-DMF systems was studied by the methods of conductometry and dynamic light scattering. The sizes (radii) of the aggregates formed and the critical micelle concentrations were determined. The catalytic activity for these systems in the hydrolisys of phosphorus acid esters was shown. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 924–931, May, 2007.