Leonid N. Markovsky

Host–guest interactions of calix[4]resorcinarenes with benzene derivatives in conditions of reversed‐phase high‐performance liquid chromatography. Determination of stability constants

Reversed-phase high-performance liquid chromatography [LiChrosorb RP-18,UV detection at 254 nm and acetonitrile-water (86:14,v/v) as mobile phase] was applied to studies of the host–guest complexation of tetraalkylcalix[4]resorcinareneoctols and their upper rim phosphoryl, sulfonyl and dialkylaminomethyl derivatives with some aromatic guests in the mobile phase. It was shown that the formation of the inclusion complexes results in changes in the retention of aromatic guests and improves their separation. Stability constants of the complexes were calculated from the dependences of the l/k′ values of the aromatic guest on the concentration of the calix[4]resorcinarene in the mobile phase. The molecular structure of 4,6,16,18-tetrahydroxy-10,12,22,24-tetrakis(dipropoxyphosphoryloxy)-2,8,14,20-tetramethylcalix[4]resorcinarene (12) was determined. Crystal data for 12 are P21/n,a  =  16.708(9) A, b  =  18.683(6) A, c  =  20.243(5) A, β  =  95.75(3)°, V  =  6287(4) A3 and Z  =  4. Compound 12 exists in a boat conformation, in which two opposite unsubstituted resorcinol rings of the macrocyclic skeleton lie in the plane formed by four methine bridges and two diphosphorylated rings are perpendicular to the plane.

PREPARATION AND REACTIONS OF 2,4,6-TRIS(TRIFLUOROMETHYL)PHENYLAMINE

Abstract Starting from R f H ( 1 ) [R f = l,3,5-tris(trifluoromethyl)phenyl] R f NH 2 ( 6 ) is obtained in a four-step synthesis. The amine 6 reacts with chlorotrimethylsilane in the presence of DBU (J, 8-diazabicyclo(5,4,0)undec-7-ene) forming the monosilylated and the bissilylated amines 7 and 8 . The potassium salt of 7 reacts with SiCl 4 yielding R f N(SiCl 3 ) 2 ( 10 ). The single crystal X-ray structure of 10 is reported.

Synthesis and Binding Properties of Phosphorus-Containing Calixarenes and Calixresorcinarenes

Abstract Full and regioselectively phosphorylated calix[4]arenes and calix[4]resorcinarenes were synthesized by Nickel catalyzed Arbuzov reaction of para-bromosubstituted calixarenes as well as by reaction of the hydroxyl-derivatives with chlorophosphates. Stereochemistry, chemical transformations, and complexation of the titled phosphorus-containing macrocycles were examined.

Inclusion Compounds of Octakis-Diphenoxy-phosphoryloxy-, Octakis-Tosyloxytetra methylcalix[4] Resorcinarenes and Bis-(Diisopropoxyphosphoryl) Dibenzo-18-Crown-6 with Benzene Derivatives

Abstract Crystalline complexes of composition 1:1 of calixresorcinarenes 1 and 2, and crown ether 3, with a number of benzene derivatives have been synthesized. By means of X-ray crystallography and NMR-spectroscopy the structures of the host molecules and the complexes in the solid state and solutions have been investigated. It was shown that calixresorcinarenes 1 and 2 exist in the boat conformation both in the solid state and in solution. The guest molecules in complexes of calixresorcinarenes 1 are located within channels in the host crystal lattice. The selectivity of binding of benzene derivatives was investigated and the role of the hydrogen bonds and CH … π interaction was estimated.

Phosphorus-Containing Macrocyclic “Host”-Molecules. Synthesis, Structure and Properties

Abstract Macrocyclic “host”-molecules (crown-ethers, calixarenes, calixresorcynolarenes and cyclotricate- chylenes) functionalized with exocyclic phosphorus groups are discussed.

X-ray and NMR investigation of 25,27-dihydroxy-26,28-bis(diethoxyphosphoryloxy)-tert-butylcalix[4]arene in the1,2-alternate conformation

The crystal structure of 25,27-dihydroxy-26,28-bis(diethoxyphosphoryloxy)-tert-butylcalix[4]arene (1) (hexane solvate, 1:1) was determined by x-ray crystallography. The crystal data are P21/n, a  =  12.652(1) A, b  =  12.564(2) A, c  =  18.781(4) A, β  =  105.56(1)°, V  =  2876.0(8) A3, Z  =  2. In this complex the molecule adopts a 1,2-alternate conformation. Both the calixarene and hexane molecules are centrosymmetric. The phenol units in the asymmetric part of the calix are inclined with respect to the main macrocyclic plane by 115.46(6)° and 128.01(7)° for the phosphorylated and the non-phosphorylated ring, respectively. Self-inclusion of the ethyl chains in the half-cavities is observed. One intramolecular O—H…O and several intermolecular C—H…O hydrogen bonds are present. In the 1H NMR spectrum one average AX spin system for methylene bridge protons can be interpreted as fast (on the NMR time-scale) interconversion of non-phosphorylated phenol fragments.

Phosphorotropic Isomerization of Diphosphoryl Calix[4]Arenes in Synthesis of Their Chiral Derivatives

Abstract Calixarenes are synthetic macrocycles obtainable by joining phenolic units through methylene bridges. Since they have original molecular architecture, they are considered to be important starting materials in design novel host-molecules for molecular recognition and separation. Introduction of chirality into calixarenes seems to be of great value for development of new class of artificial enzymes. Chira1 lower rim trisubstituted calix[4]arenes 2 possessing no plane of symmetry were synthesized with good yields by one-pot procedure consisted in successive treatment of 1,3-di-phosphorylcalix[4]arenes 1 in cone conformation with 1 eq. NaH and benzoyl chloride or methyl monobromoacetate.

Synthesis and Properties of Exo-Phosphorylated Benzocrown-Ethers

Abstract The crown ethers 1,2, containing exocyclic phosphorus groups, were obtained1 by the interaction of, bromo-, iodo-, and sulpamidoderivatives of mono- and dibenzocrown ethers with esters of trivalent phosphoric acids, alkenylphos-phonates and phosphorus pentachloride in presence of metal catalysts. On the basis of these compounds the crown ethers with various substitutes at phosphorus atom (including the polymeric ones) were synthesized. Further reaction of the crown ether 1 (X = “-” R = Ph, R′ = H) with glycol dichlo-rides gave first phosphorus-containing bis-crown ethers 3.