Irina R. Knyazeva

Cloud point extraction of lanthanide(III) ions via use of Triton X-100 without and with water-soluble calixarenes as added chelating agents

The use of water-soluble calixarenes: p-sulfonato thiacalixarene (ST), tetra-sulfonatomethylated calix[4]resorcinarene (SR), calix[4]resorcinarene phosphonic acid (PhR) as chelating agents in cloud point extraction (CPE) of La(III), Gd(III) and Yb(III) ions using Triton X-100 as non-ionic surfactant is introduced. The data obtained indicate that both complexation ability and structure of calixarenes govern the extraction efficiency of lanthanides. In particular ST and SR, forming 1:1 lanthanide complexes with similar stability in aqueous media, exhibit different extractability when used as chelating agents in CPE. First synthesized PhR was found to be the most efficient chelating agent exhibiting pH-dependent selectivity within La(III), Gd(III) and Yb(III) in CPE.

New Calix[4]Resorcinols with Thiophosphoryl-Containing Fragments

Abstract The condensation of thiophosphorylated aldehydes 1 and 2 with resorcinol and its derivatives leads to the formation of the new type of calix[4]resorcinols with four thiophosphoryl groups inserted to the substituents located in methylidene bridges of the molecule. The conformation of these compounds was found to be “flattened partial cone” or “chair,” which was determined by NMR methods and a single-crystal X-ray diffraction study. GRAPHICAL ABSTRACT

Oxygen reduction reaction catalyzed by nickel complexes based on thiophosphorylated calix[4]resorcinols and immobilized in the membrane electrode assembly of fuel cells

The catalytic activity of the nickel complexes of thiophosphorylated calix[4]resorcinols for oxygen reduction in a polymer electrolyte membrane fuel cell (PEMFC) has been studied. The conformation of the macrocyclic ligand determines the morphology and catalytic properties of the resulting organometallic species.

Nickel Complexes Based on Thiophosphorylated Calix[4]Resorcinols as Effective Catalysts for Hydrogen Evolution

Nickel complexes of thiophosphorylated calix[4]resorcinols showed high catalytic activity for hydrogen evolution from acidic solutions and stability in the electro-assisted catalysis at the surface of both glassy carbon and Hg-pool electrodes. The conformation of the macrocyclic ligand determines the dimensionality and shape of the catalytically active species generated on the electrode.

Single step preparation and conformational analysis of novel thiophosphorylated ligands based on calix[4]resorcinol matrix

We have synthesized novel calix[4]resorcinols with four 2-thioxo-1,3,2-dioxaphospholane groups introduced in aromatic substituents in the methylidene bridges of macromolecules by the condensation of new thiophosphorylated benzaldehyde with resorcinol and its derivatives in acidic media with high yields. The formation of only one rctt isomer with corresponding chair conformation is observed, which was determined by 2D NMR-experiments.

Synthesis and Properties of Novel Calix[4]Resorcinols Containing Phosphonium Substituents

Abstract Condensation of resorcinol and its derivatives with novel phosphonium-substituted acetals under conditions of acidic catalysis yields either calix[4]resorcinols containing four phosphonium fragments or phosphonium salts including diarylmethane moiety depending on the structure of the phosphorus-containing reagent. The latter, in turn, undergo condensation with propionic aldehyde forming new calix[4]resorcinols with alternating phosphonium and ethyl substituents, which have remarkable surface-active properties. GRAPHICAL ABSTRACT

New triamidophosphonium acetals and their condensation with resorcinol and its derivatives

A number of new acetals bearing phosphonium moieties with P-N bonds were prepared. Their condensation with resorcinols in acidic water-alcohol solutions was studied, which led to new phosphonium salts having a diarylmethane fragment.

New P-Containing Linear and Macrocyclic Polyphenols

Abstract We synthesized new phosphorus-containing linear and macrocyclic polyphenols using organic compounds containing phosphorus-carbon bonds and the phosphorus atom of various coordination, and also with reactive acetal, aldehyde, vinylethoxy, and methylene quinone fragments as starting materials. These achievements are briefly summarized.

Electrochemical synthesis of the calix[4]resorcinol nickel complexes modified with thiophosphoryl fragments

Nickel complexes of 1:1 composition with calix[4]resorcinols (L) modified with thiophosphyl fragments were synthesized. In the process of electrochemical reduction these complexes are capable of providing spherical homogeneous Ni(0)L particles with a narrow size distribution, stable both on the electrode and in the solution. The redox properties of the metal complexes were studied. The dimensions of the complexes obtained were estimated using the atomic force microscope (AFM) equipped with an electrochemical attachment.

Calix[4]resorcinarenes containing dithiophosphate fragments on the lower rim of the molecule

Synthesis methods of calix[4]resorcinarenes are known to be based on the tetramerization reactions of aliphatic and aromatic aldehydes with resorcinol and others aromatic phenols in acidic water-alcohol media [1, 2]. We developed a new one-stage synthetic approach to calix[4]resorcinarenes phosphorylated on the lower molecular rim by reaction of resorcinol and its derivatives with available α-phosphorylated acetals and ethoxyvinylphosphonates under the acid catalysis conditions [3–6]. We found that this method can be used to obtain calixarene including dithiophosphate fragments on the lower molecule rim. It is achieved by bringing О,О-diethyl-S-[β-(О,О-diethyl)]ethyldithiophosphate II into the reaction with resorcinol and its derivatives Iа and Ib [7] and by carrying out the process in trifluoroacetic acid. DOI: 10.1134/S1070363209120251