the complexation reactions between tl+ and pb2+ ions and crown ethers 12-crown-4(12c4), 15-crown-5 (15c5), benzo-15-crown-5 (b15c5), 18-crown-6 (18c6), dicyclohexyl-18-crown-6 (dc18c6) and aza-18-crown-6 (a18c6) were studied in 90% acetonitrile and 90% ethanol solutions at 25 °c, using an a.c. polarographic technique. the stoichiometry and stability of the complexes were determined by monitorin...

Complexes of benzo-15-crown-5 macrocycle with Li+ and Cs+ ions were investigated by 7Li and 133Cs NMr in a number of nonoqueous solutions. The resulting 1:1 complex with Li+ ion was found to be much more stable than that with Cs+ ion. With the exception of pyridine solutions the stabilities of the complexes varied inversely w...

the interaction between benzo-15-crown-5 (b15c5), dibenzo-18-crown-6 (db18c6), dibenzyl-daza-18crown-6 (dbzda18c6), n-phenyl-aza-15-crown-5 (npha15c5) and dibenzopyridine-18-crown-6 (dbpy18c6) with π-acceptor 2,3-dichloro-5,6-dicyanobenzoquinone (ddq) in chloroform solution was studied spectrophotometrically. the interaction of b15c5-ddq and db18c6-ddq caused the formation of 1:1 charge transfe...

The interaction between benzo-15-crown-5 (B15C5), dibenzo-18-crown-6 (DB18C6), dibenzyl-daza-18crown-6 (DBzDA18C6), N-phenyl-aza-15-crown-5 (NPhA15C5) and dibenzopyridine-18-crown-6 (DBPy18C6) with π-acceptor 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) in chloroform solution was studied spectrophotometrically. The interaction of B15C5-DDQ and DB18C6-DDQ caused the formation...

The various association constants, bnm and Knm, of NaCl and NaClO4 with [12]crown-4, [15]crown-5, [18]crown-6, benzo[15]crown-5, benzo[12]crown-4, dibenzo[18]crown-6 and dinaphtho[18]crown-6 have been estimated in a mixture of dioxane/water (80/20) using a sodium ion selective electrode (ISE). The constants have been estimated using 1=ðKnm1⁄2Lo n1m21Þ5 ð1 2 nP 0Þn ð1 2 mP 0Þm=P 0; where P 0, th...

The complexation reactions between Tl+ and Pb2+ ions and crown ethers 12-crown-4(12C4), 15-crown-5 (15C5), benzo-15-crown-5 (B15C5), 18-crown-6 (18C6), dicyclohexyl-18-crown-6 (DC18C6) and aza-18-crown-6 (A18C6) were studied in 90% acetonitrile and 90% ethanol solutions at 25 °C, using an a.c. polarographic technique. The stoichiometry and stability of the complexes we...

complexes of benzo-15-crown-5 macrocycle with li+ and cs+ ions were investigated by 7li and 133cs nmr in a number of nonoqueous solutions. the resulting 1:1 complex with li+ ion was found to be much more stable than that with cs+ ion. with the exception of pyridine solutions the stabilities of the complexes varied inversely with the gutmann donor number of the solvents. some indirect evidence f...

Study of interaction between catechol and tetraethylene glycol dichloride in the n-butanol media, resulting with benzo-15-crown-5 production. Production of nitroand amino-derivatives of benzo-15-crown-5. Determination of their thermogravimetric characteristics. keywords: benzo-15-crown-5, catechol, tetraethylene glycol dichloride, crown ether, gas liquid chromatography, chromate-mass spectrometry

Compounds consisting of [M(1,2-disila-[3n]crown-n)]2+ (M = Mg, Ca, Sr, Ba; n = 5, 6) and [Ba(1,2-disila-benzo[18]crown-6)]2+ cations and different anions were obtained by equimolar reaction of the hybrid disila-crown ethers 1,2-disila[15]crown-5 (1), 1,2-disila[18]crown-6 (2) and 1,2-disila-benzo[18]crown-6 (7) with alkaline earth metal salts. Even with strongly coordinating anions such as Br- ...