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Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(-)-1-phenyl-ethyl ammonium percholorate
(R Oldenbourg Verlag, 2003) Özbey, S; Kaynak, FB; Togrul, M; Demirel, N; Hosgören, H
A new type of inclusion complex, S(-)-1 phenyl ethyl ammonium percholorate complex of R-(-)-2-ethyl-N-benzyl-4,7,10,13-tetraoxa-1-azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group P2(1) with cell dimensions a = 10.0000(8), b - 12.281(2), c = 12.331(1)Angstrom, beta = 102.052(7), Z = 2. The host-guest complex is held together by a strong system of hydrogen bonds between the two protons of the ammonium ion as well as the nitrogen and four oxygen atoms of the crown ether The C-O and C-C distances of the 15-membered ring average 1.418 and 1.501 Angstrom while the O-C-C and C-O-C angles average 110.2 and 113.3degrees. The average N-C distance is 1.476 Angstrom.
Effect of 1,3-diol structure on the distribution of boron between CHCl3 and aqueous phase
(Marcel Dekker Inc, 2003) Karakaplan, M; Tural, S; Sunkür, M; Hosgören, H
The various new aliphatic 1,3-diols, containing primary, secondary, tertiary, and mixed of these groups, were synthesized and used for the solvent extraction of boron. Diols (8a, 8b, 9, 10a, 10b, 11, 12a, 12b, 13) were prepared from (beta-hydroxy carbonyl compounds 1-7. The fixed standard solution of boric acid of 1.00x10(-2) M was extracted with 0.1 M and 0.5 M diols at equilibrium pH of 2 and at constant ionic strength (I=0.5). The best extracting reagent was found to be 11, which is a primary-tertiary class of -OH groups and methyl groups as a substituent on the second carbon of 1,3-diol.
The effect of benzo substitution on complexation of diaza 18-crown-6 ethers derivatives with NaClO4
(Springer, 2005) Köylü, MZ; Demirel, N; Polat, FD; Yilmaz, A; Hosgören, H; Balci, M
The complexation of the crown ethers with Na+ ion was studied. H-1-NMR chemical shifts are discussed in terms of structural modi. cation as well as also binding studies with UV-vis spectra were included.
Effect of long-chain amines on the extraction of boron from CaCl2 brine with CTMP in petroleum benzine
(Marcel Dekker Inc, 1999) Yurdakoç, M; Karakaplan, M; Hosgören, H
The effect of TOA (tri-n-octylamine), TOMA (tri-n-octylmethylammonium iodide), DEDA (N,N'-didodecylethylenediamine), DEDMA (N,N'-didodecyl-N,N'-tetramethylethylene-diammonium diiodide), and NDM (N-dodecylmorpholine) upon the solvent extraction of boron from CaCl2 brine with CTMP [2-chloro-4(1,1,3,3,-tetramethylbutyl)-6-methylolphenol] in petroleum benzine has been studied. In order to extract boron effectively and reject other cations such as Ca2+, the extraction of boron with CTMP was investigated in terms of extractant, the concentration of an amine, and solvent polarity. The results show that in the presence of long-chain amines, boron extraction with CTMP in all solvent systems was shifted To a more acidic pH range. Larger extraction, hence distribution, and an increase in selectivity are observed when CTMP is used together with long-chain amines and their ammonium salts in petroleum benzine.
The enantiomeric recognition of chiral organic ammonium salts by chiral monoaza-15-crown-5 ether derivatives
(Pergamon-Elsevier Science Ltd, 2004) Turgut, Y; Sahin, E; Togrul, M; Hosgören, H
Novel chiral monoaza-15-crown-5 ether derivatives 1 and 2 were prepared frorn L-phenylalaninol and L-leucinol, respectively. The effect of the substituent at the stereogenic center on chiral recognition and enantioselectivity were investigated. Binding constant (K), free-energy changes (-DeltaG(0)), enthalpy change (DeltaH), and entropy change (DeltaS) values were determined with enantiomers of organic ammonium salts by a titration UV-vis method in CHCl3. (C) 2004 Elsevier Ltd. All rights reserved.
Enantioselective transport of amino acids as their potassium and sodium salts by optically active diaza-18-crown-6 ethers having arene sidearms
(Pergamon-Elsevier Science Ltd, 2004) Demirel, N; Bulut, Y; Hosgören, H
The enantioselective transport of amino acids as their sodium and potassium salts has been investigated by optically active diaza crown ethers. The reversed enantioselectivity of chiral crown ether 1 was observed. (C) 2004 Elsevier Ltd. All rights reserved.
New copper(II), manganese(III), nickel(II) and zinc(II) complexes with a chiral quadridentate Schiff base
(Springer, 2002) Temel, H; Hosgören, H
A chiral Schiff base ligand (H2L) was obtained by condensing 2-hydroxynaphthalene-1-carbaldehyde with substituted (1R,2R)-(-)-diaminocyclohexane. Chiral Schiff base complexes [CuL], [NiL], [ZnL] and [MnLOH] have been synthesized and characterized by elemental analyses, Lambda(M), i.r., u.v.-vis. and H-1-n.m.r. and magnetic measurements.
A practical synthesis of chiral 3-aryloxy-1,2-propanediols
(Science Reviews 2000 Ltd, 2005) Karakaplan, M; Turgut, Y; Hosgören, H
Chiral 3-aryloxy-1,2-propanediols (1-5) of > 96% ee were obtained in high yield by the nucleophilic addition of substituted phenols to chiral glycidol in the presence of piperidine hydrochloride as catalyst.
Saligenin derivative borocryptands
(Science Reviews Ltd, 2003) Togrul, M; Sünkür, M; Kaynak, FB; Hosgören, H; Özbey, S
A new lithium receptor based on the combination of the [11] macrocyclic core and two 4-tert-butyl saligenin units was designed and prepared.
The solvent extraction of boron with synthesized aliphatic 1,3-diols
(Taylor & Francis Inc, 2004) Karakaplan, M; Tural, S; Tural, B; Turgut, Y; Hosgören, H
A variety of aliphatic 1,3-diols (4a-c, 5a-c, 6a-c) was synthesized from beta-hydroxy carbonyl compounds (1-3) for potential use in the solvent extraction of boron. Primary-secondary and primary-tertiary alcohol structures of 1,3-diols substituted with isopropyl, isobutyl, and isopentyl groups have been demonstrated to be very efficient for the solvent extraction of boric acid from aqueous solutions. The extraction ability of 2,2,5-trimethyl-1,3-hexanediol (5b) was investigated as a function of 5b concentration, solution pH, solvent properties, and stripping conditions. Extraction efficiency increased with increasing concentration of 5b, and the best extraction of boron (96.8%) was found to be at an equilibrium pH of 2 with 0.5 M of 5b. Chloroform, toluene, chlorobenzene, 2-octanol, and n-amyl alcohol were found to be suitable solvents for the solvent extraction of boron. The boron complex can be recovered from the organic phase by treatment with an aqueous solution of sodium hydroxide. The highest ratio (96.7%) of boron was recovered by 0.1 M of sodium hydroxide solution.
Synthesis and characterization of Na+ and Ba2+ complexes with some lipophilic diaza-18-crown-6 derivatives
(Springer, 1998) Temel, H; Hosgören, H; Çakir, Ü; Boybay, M
The solid and stable Na+ and Ba2+ complexes of 7,16-Dibenzyl-4,7,10,13-tetraoxa-7, 16-diazacyclooctadecane; 7, 16-Dihexyl-4,7,10,13-tetraoxa-7,16-diazacyclooctadecane; 7,16-Dihep-tyl-4,7,10,13-tetraoxa-7,16-diazacyclootadecane, 7,16-Dioctyl-4,7, 10,13-tetraoxa-7, 16-diazacycloctadecane; 7,16-Dinon yl-4,7,10,13 -tetraoxa-7,16-diazacyclooctadecane; 7,16-Didodecyl-4,7, 10, 13-tetraoxa-7,16-diazacyclooctadecane were prepared. The complexes were investigated using Elemental Analysis, IR, H-1 NMR, C-13 NMR spectroscopy. H-1 and C-13 chemical shifts observed in complexes are discussed in terms of conformational changes on the macrocycles.
Synthesis and characterization of Na+, K+, Ca2+, Ba2+, Sr2+, and Pb2+ complexes with some lipophilic diaza-18-crown-6 derivatives
(Marcel Dekker Inc, 2002) Temel, H; Hosgören, H; Boybay, M
In this study, the complexes of 7,16-Dibenzyl-4,7,10,13-tetraoxa-7,16-diazacyclooctadecane; 7,16-Dihexzyl-4,7,10,13tetraoxa-7,16-diazacyclooctadecane; 7,16-Diheptyl-4,7,10,13tetraoxa-7,16-diazacyclooctadecane; 7,16-Dioctyl-4,7,10,13tetraoxa-7,16-diazacyclooctadecane; 7,16-Dinonyl-4,7,10,13tetraoxa-7,16-diazacyclooctadecane; 7,16-Didodecyl 4,7,10, 13-tetraoxa-7,16-diazacyclooctadecane with Na+, K+, Ca2+, Ba2+, Sr2+ and Pb2+ were prepared by using perchlorates salts. Their complexes were produced by adding the solution of metal salts in ethyl alcohol to the solution of ligand in ethyl alcohol. The complexes obtained were filtered and washed with ethyl alcohol and recrystallizied in ethyl alcohol and dried in vacuum. Their complexes were investigated by using Elemental Analysis, and infrared (IR). Observed H-1 NMR,C-13 NMR, and C-13 chemical shifts are discussed in terms of conformational changes of the macrocycle.
Synthesis and complexation of new substituted dibenzodiaza macrocyclic diester compounds
(Taylor & Francis Inc, 2002) Topal, G; Temel, H; Çakir, Ü; Ugras, HI; Karadeniz, F; Hosgören, H
The synthesis of some new precoursers that contain substituted benzo units and their use in the preparation of azama-crocyclic diester compounds are reported. These precoursers and ligands were characterized by Elemental analysis, H-1 and C-13 NMR spectroscopy, and IR spectroscopy. The complexation constants Ke and DeltaGdegrees values for the diesters with several transition metal cations (Ag+, Zn2+ and Cu2+) in a dioxan-water system using a conductometric method at 25degreesC are also reported.
Synthesis of chiral crown ethers and complexation with chiral protonated amine compounds
(Springer, 2004) Togrul, M; Demirel, N; Kaynak, FB; Özbey, S; Hosgören, H
The X-ray crystal structure of IX, perchlorate salt of R-(-)-2-ethyl-N-benzyl-4,7,19,13-tetraoxa-8,9-benzo-1-azacyclopentadec-8-ene has been determined. In the molecule, the protonated nitrogen atom participates in two N-(HO)-O-... hydrogen bonds. The unusually high proton affinity of aza crown ether leads to the formation of diastreomer instead of complex formation with chiral R-(+)-1-phenyl ethyl ammonium perchlorate and S-(-)-1-phenyl ethyl ammonium perchlorate. The complex ability of host ethers was evaluated in terms of structural modification.
Synthesis of chiral monoaza-15-crown-5 ethers from L-valinol and the enantiomeric recognition of chiral amines and their perchlorates salts
(Pergamon-Elsevier Science Ltd, 2003) Turgut, Y; Hosgören, H
A practical synthesis of chiral monoaza-15-crown-5 ethers I and 2 has been achieved from L-valinol. The molecular recognition by these chiral crown ethers for (RS)-alpha-phenylethylamine, (RS)-alpha-(1-naphthyl)ethylamine and their perchlorate salts has been characterized by UV-vis. (C) 2003 Elsevier Ltd. All rights reserved.
Synthesis of new chiral diaza 18-crown-6 ethers from chiral amines
(Science Reviews 2000 Ltd, 2003) Demirel, N; Turgut, Y; Hosgören, H
Practical syntheses of versatile building blocks of crown ethers 1 and 2, chiral amine precursors 3-6 and chiral diaza 18-crown-6 ethers 7-12 are reported starting from chiral amines.
Synthesis of novel chiral C2-symmetric diaza-18-crown-6 ether derivatives and their enantioselective recognition of amino acid derivatives
(Springer, 2006) Turgut, Y; Demirel, N; Hosgören, H
New chiral diaza-18-crown-6 ether derivatives, 5 and 6 were synthesized from (R)-(-)-2-amino-1-butanol. These chiral artificial receptors exhibit pronounced chiral recognition toward the enantiomers of L- and D- amino acid derivatives. The highest enantioselectivity was observed in the case of Trp-OMe center dot HCl (K-D/ K-L= 12.5).
Synthesis of novel chiral monoaza-15-crown-5 ethers and their molecular recognition of amino acid esters
(Science Reviews 2000 Ltd, 2004) Turgut, Y; Isgin, ES; Hosgören, H
The chiral monoaza-15-crown-5 ethers 4 and 5 were prepared from L-phenylalaninol and L-leucinol, respectively. The molecular recognition of these chiral crown ethers for L-amino acid ethyl esters was characterised by UV-visible spectroscopy. Binding constants (K-a), free-energy changes (-DeltaGdegrees), enthalpy changes (DeltaH) and entropy change (DeltaS) values were determined for hosts 4 and 5 with L-amino acid ethyl ester hydrochlorides in CHCl3.
Synthesis of R-(-)-2-ethyl-N-benzyl (benzo-monoaza-15-crown-5) and the crystal structure of its sodium perchlorate complex
(Springer, 2003) Özbey, S; Kaynak, FB; Togrul, M; Demirel, N; Hosgören, H
A new complex of a chiral monoaza-crown ether, [R-(-)-2-ethyl-N-benzyl-4,7,10,13-tetraoxa-8,9-benzo-1-azacyclopentadec-8-ene.NaClO4], has been prepared and studied by x-ray diffraction. The compound crystallizes in space group P2(1) with cell dimensions a = 8.721(1), b = 16.318(2), c = 8.905( 1) Angstrom, beta = 100.80(1)degrees. The sodium cation is heptacoordinated and located significantly out of the best plane of the macrocycle ring. The donor atoms of the macrocycle are in the half-chair arrangement.
Synthesis of R-(-)-2-ethyl-N-benzyl (monoaza-15-crown-5) and the crystal structure of its sodium perchlorate complex
(Springer, 2001) Özbey, S; Hosgören, H; Turgut, Y; Topal, G
A new complex of a chiral monoaza-crown ether, [R-(-)-2-ethyl-N-benzyl-4,7,10,13-tetraoxa-1-azacyclopentadeceane) NaClO4], has been prepared and studied by x-ray diffraction. The compound crystallizes in space group P2(1) with cell dimensions a = 9.480(1), b = 15.978(2), c = 15.816(2) Angstrom, beta = 105.51(1)degrees, Z = 4. The final R value is 0.055 for 2711 observed reflections and 540 parameters. There are two molecules in the asymmetric unit labelled A and B. The sodium ion is hexacoordinated. The average values for the Na-O-eth (etheric) distances are 2.364(6), 2.317(7) Angstrom and the Na-N distances are 2.679(6), 2.611(7) Angstrom; the Na-O(ClO4) contacts are 2.497(7) and 2.257(10) Angstrom, for A and B, respectively.

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