........................................................................................................................... III ACKNOWLEDGEMENTS ........................................................................................................ VI LIST OF FIGURES ................................................................................................................. XIII LIST OF T...

Silicon containing pyridine and quinoline sulfides have been prepared using phase transfer catalytic system thiol/alkyl halide / solid KOH/18-crown-6 / toluene. The target S-ethers were isolated in yields up to 81%. The cytotoxicity of the synthesized compounds was studied. Among pyridine sulfides S-[3-(1-methyl- 1-silacyclohexyl)propyl] derivatives 5e and 6e exhibit the highest cytotoxicity. A...

A novel, efficient, time-saving and reliable radiolabeling procedure via nucleophilic substitution with [(18)F]fluoride is described. Different radiolabeled aliphatic and aromatic compounds were prepared in high radiochemical yields simply by heating of quaternary anilinium, diaryliodonium and triarylsulfonium [(18)F]fluorides in suitable solvents. The latter were obtained via direct elution of...

To probe the influence of structural variation within dibenzo-16crown-5-oxyacetic acids upon the selectivity of alkali metal cation separations by solvent extraction and liquid membrane transport processes, studies have now been conducted in homogeneous solution by NMR spectroscopy and titration calorimetry and in the solid state. Condensation polymerization of such proton-ionizable lariat ethe...

Making one out of two: Dimeric boraza-crown ethers bridge the gap between metallacrowns and aza-crown with a strikingly simple synthesis. Dioxazaborocanes react alkoxides to form corresponding anionic boronates, which combine dimers upon ring-opening reactions. The presence was proven in solid state solution by X-ray crystallography NMR spectroscopy, respectively. influence counterion on stabil...

Herein, the characterization and reactivity of metalated arsinidenyl (SIDipp)AsK (1 a) is described. This compound was obtained via deprotonation saturated “parent arsinidene” (SIDipp)AsH (1) with strong base benzyl potassium appears as pyrophoric, insoluble, red solid. The ability crown ethers to improve solubility metal compounds through complex formation has been used obtain crystals (SIDipp...

Transport behaviour of (137)Cs from nitric acid feed was investigated using cellulose triacetate plasticized polymer inclusion membrane (PIM) containing several crown ether carriers viz. di-benzo-18-crown-6 (DB18C6), di-benzo-21-crown-7 (DB21C7) and di-tert-butylbenzo-18-crown-6 (DTBB18C6). The PIM was prepared from cellulose triacetate (CTA) with various crown ethers and plasticizers. DTBB18C6...

To date, proton-conducting organic crystalline materials based on crown ethers have rarely been investigated.

Analytical equations were derived for the extraction of univalent metal salts (MA) by crown ethers (L) into polar diluents. Then, NaMnO4 was extracted at 25 C by benzo-15-crown-5 and -18-crown-6 ethers (B15C5 and B18C6) from a water (w)-phase into a 1,2-dichloroethane (DCE)-one. So, the extraction constants of Kex1 and Kex2 were determined, where Kex1 = [NaLMnO4]DCE/[Na][L]DCE[MnO4] and Kex2 =...