F. Kh. Karataeva

Structure of hyper-branched polyester polyol BOLTORN H2O-COOH. NMR data

The methods of one- and two-dimensional 1H and 13C NMR spectroscopy have been used to study the structure of hyper-branched polyester polyol BOLTORN H2O-COOH and complex Co12[BH20(COOH)] on its basis. It was shown that both compounds have non-stereoregular structure. Paramagnetic ions Co(II) are coordinated both on the surface of the molecule and near the core.

Data of one- and two-dimensional NMR spectroscopy in the study of structure and nature of associations of hyperbranched polyester polyol Boltorn H20-OH

Structure of the hyperbranched polyester of the polyol BOLTORN H20-OH was studied by one- and two-dimensional 1H and 13C NMR spectroscopy in combination with the IR spectroscopy and semiempirical quantum-chemical calculations (method AM1). The polyol structure was shown not to be stereoregular. Three basic types of H-bonding interactions of intra- or intermolecular nature were revealed: C=O...HO, OH...OH, and C=O...HO...HO.

New materials based on tubular nanodimensional structures 1. Synthesis, structural studies and determination of interproton distances in solutions of functionalized thiacalix[4]arenes according to NMR spectroscopic data (NOESY)

New derivatives of p-tert-butylthiacalix[4]arene were synthesized. The conformation of the macrocycles and interproton distances in the synthesized thiacalix[4]arenes in solutions were determined by NMR spectroscopy. p-tert-Butylthiacalix[4]arene distally disubstituted at the lower rim adopts the cone conformation, and the tetrasubstituted products are formed in the 1,3-alternate conformation.

Reaction of 4,5-dimethyl-2-(2-oxo-1,2-diphenylethoxy)-1,3,2-dioxaphospholane with hexafluoroacetone: formation of isomeric caged phosphoranes with phosphorus–carbon and phosphorus–oxygen bonds

Abstract4,5-Dimethyl-2-(2-oxo-1,2-diphenylethoxy)-1,3,2-dioxaphospholane bearing the carbonyl group at the γ-position to the phosphorus atom reacted with hexafluoroacetone to give regio- and stereoisomeric caged phosphoranes with phosphorus–carbon and phosphorus–oxygen bonds.

One- and two-dimensional NMR study of structure of 1,2-disubstituted p-tert-butylthiacalix[4]arene containing amide fragment

The structure of 5,11,17,23-tetra-tert-butyl-25,27-dihydroxy-26,28-bis[N-(4′-nitrophenyl)aminocarbonylmethoxy] thiacalix[4]arene I was examined by 1D and 2D (NOESY) 1H and 13C NMR methods in a CDCl3 solution using numerical simulation (semi-empirical quantum-chemical calculations, PM3 method). Compound I was found to exist in the 1,2-alternate conformation, where bulky substituents OCH2C(O)· NHPhNO2 are in the endo-position relative to the macrocycle cavity.

Polydentate Nanoplatform Based on Hyperbranched Polyol Boltorn

In chemistry and technology now is rapidly developing a direction connected with the synthesis of nano-size hyperbranched polymers (HBP) and related functional derivatives possessing a wide range of practically useful properties [1, 2]. Nontoxic hyperbranched polyols of “Boltorn Н” series are promising objects for obtaining the metallocomplex compounds of biomedical application, with the polydentate polyol platform as a ligand [3, 4]. However, the complexes of “Boltorn Н” with the d-metal ions are very unstable. This may be a consequence of intraand intermolecular hydrogen bonding of hydroxy groups of the molecule that decreases significantly their steric accessibility and capability of complex formation [5, 6]. A route for overcoming this problem is the modification of HBP by means of substitution of OH groups by the groups more active toward metal ions.

Structure and molecular lability of N-(thio)phosphoryl(thio)amides: XVII. Intramolecular transformations of N,N′-bis(thio)phosphoryl(thio)ureas with the open-chain fragment in DMSO solution

By means of the 1H, 13C, and 31P NMR spectroscopy structure and intramolecular transformations of N,N′-bis[diisopropoxythiophosphorylaminothiocarbonyl]-1,7-diaminoheptane in 3–10% DMSO solutions were studied. High lability of molecule with the realization of two conformers (linear and pincer-like) of macromolecule, of the proton imide-imide exchange, and of different tautomeric forms was proved.

Formation of a Polynuclear Cobalt(II) Complex on a Polydentate Nanoplatform of Carboxylated Boltorn H20

A method of synthesis of a polynuclear cobalt(II) complex with carboxylated Boltorn H20, a hyperbranched polyol of second generation, has been suggested. The logarithm of stability constant and the composition of the complex species BH20(OC(O)CH2CH2COO)12Co12 in a 50% acetone solution have been calculated from the electronic absorption spectra: logβ = 13.7 ± 0.2 and the composition M : L = 12 : 1. The IR spectroscopy and NMR (13C and 1H) point to the coordination of Co(II) ions not only at the surface of the molecule but also near its core.

One- and two-dimensional NMR study on structural features of polyester derived from Boltorn H20-OH polyol and maleic acid

The structure of hyperbranched Boltorn H20-OH maleate was studied by one- and two-dimensional NMR spectroscopy and AM1 simulation. The polyester was found to have a non-stereoregular structure where two linear branches, as well as terminal and dendritic branches, are brought together in pairs.

Structure and intramolecular mobility of N-(thio)phosphoryl(thio)amides: XVI. 1H, 13C and 31P NMR study of intramolecular dynamics of N,N′-bis(thio)phosphoryl(thio)urea containing an open-chain fragment in CD2Cl2 and CD3CN solutions

The structure and intramolecular transitions of N,N′-bis[N-disopropoxythiophosphorylaminothiocarbonyl]-1,7-diaminoheptane in CD2Cl2 and CD3CN 3–10% solutions were studied by means of 1H, 13C, and 31P NMR spectroscopy. Combined analysis of the NMR data confirmed a high lability of the molecules with the realization of two conformational forms of the macromolecule, the amide-amide proton exchange, and existence of various tautomeric forms.