Sixteen lipophilic N-(X)sulfonyl carbamoyl lariat ethers with polyether ring sizes of 12-crown-4, 14-crown-4, 15-crown-5, and 18-crown-6 are utilized for competitive alkali metal cation extractions from aqueous solutions into chloroform. Variation of the electron-withdrawing properties of X in the series of methyl, phenyl, 4-nitrophenyl, and trifluoromethyl allows the influence of the acidity o...

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 present study was carried out by focusing on the interaction between molecular complexes crown and thiacrown ethers such as 15-crown-5 (15C5), thia-15-crown-5 (T15C5), dithia-15-crown-5 (DT15C5) with homogeneous and heterogeneous dihalogens (XY) such as I2, IBr, ICl, Br2, Cl2 in the gas phase and in dichloromethane solvent through applying density function theory (DFT) as well as Gaussian 9...

the preparation of polymer membrane selective to iron(ii) ion and its application to ion-selectiveelectrode is reported here. pvc membrane contains iron–selective n-phenylaza-15-crown-5 asionophore. the membrane electrode is highly selective to iron(ii) ion and exhibit good linearresponse over a wide concentration range of 1.0 × 10-2 to 1.0 × 10-6 m with nernstian slope of29.2 ± 0.6 mv per deca...

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...

K 2 Se5 has been prepared by crystallization from a potassium polyselenide solution in DM F. In a similar way [Na(15-crown-5)]2Se5 can be prepared by crystallization from a sodium poly­ selenide solution in D M F in the presence o f 15-crown-5. Both compounds were characterized by FIR spectroscopy as well as by X-ray structure determinations. K 2 Se5: Space group P 2,2,2,, Z 4, 1659 observed in...