• Membrane Journal
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• v.16 no.2
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• pp.133-143
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• 2006

A hollow fiber membrane containing BSA as ligand was Prepared by radiation-induced grafting GMA onto a porous polyethylene hollow fiber and subsequent reacting with DEA and TEA. The density of the DEA and TEA of the membrane were 3.4 mmol/g, 1.7r mmol/g, respectively. The DEA membrane exhibited a higher amount of than the TEA membrane. BSA was immobilized by the graft chains during the permeation of BSA solution throught the DEA and TEA membrane. The BSA was adsorbed in multilayer binding of 8 onto the DEA membrane whereas adsorption onto the TEA membrane remained constant. A two-stage stepwise BTC was observed due to independent chiral recognition for L, D-Trp solution by DEA-BSA membrane.

• Bulletin of the Korean Chemical Society
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• v.12 no.3
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• pp.332-334
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• 1991

The reaction and coordination chemistry of chiral ferrocenylaminophosphines such as 2-(diphenylphosphino)-1-(N,N-dimethylaminoethyl) ferrocene (PPFA), and 1',2-bis(diphenylphosphino)-l-(N,N-dimethylaminoe thyl) ferrocene (BPPFA), with various iron carbonyls have been investigated. PPFA reacted with iron carbonyls, Fe$(CO)_5$, $Fe_2(CO)_9$, or $Fe_3(CO)_{12}$ to give an iron complex of the type (${\eta}^1$-PPFA-P)Fe$(CO)_4$ (1) as a single product regardless the choice of the iron carbonyls. The bisphosphine ligand BPPFA afforded two products (${\eta}^1$-BPPFA-P)Fe$(CO)_4$ (2) and (${\mu}$,${\eta}^1$-BPPFA-P,P)$Fe_2(CO)_8$ (3) in which BPPFA acts as a monodentate and a bridging ligand, respectively. In all cases coordination to the -Fe$(CO)_4$ moiety is made through the phosphine rather than the amino group and, in the case of 2, the coordination is made through the phosphine substituted at the $C_5H_4$ ring to reduce the steric congestion.

• Bulletin of the Korean Chemical Society
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• v.24 no.2
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• pp.225-228
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• 2003

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.732-739
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• 1994

Asymmetric [2,3]-Wittig rearrangements of allyl propargyl ethers in hexane were performed in the presence of s-butyllithium and (-)-${\alpha}$-isosparteine which is a $C_2$-symmetric chiral ligand for the alkyllithium reagent. The reactions of (Z)-or (E)-allyl 3-trimethylsilylpropargyl ethers at -78$^{\circ}C$ showed good diastereoselectivities (74-100%) and moderate enantioselectivities (29-71%). The absolute configurations of the rearrangement products were determined by the corresponding Mosher's esters. It was found that (-)-${\alpha}$ -isosparteine induced (R) configuration at the hydroxy carbon and syn stereochemistry more favorably. The possible transition state is discussed.

• Bulletin of the Korean Chemical Society
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• v.17 no.5
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• pp.433-436
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• 1996

Cobalt(Ⅲ) complexes of trifunctional amino acid and N,N'-diethylethylenediamine-N,N'-di-α-butyrate(deedba), s-cis-[Co(deedba)(L-aa)] (L-aa=S-methyl-L-cysteine, L-aspartic acid, L-glutamic acid) have been prepared from the reaction between the s-cis-[Co(deedba)(Cl2)]- complex and the corresponding amino acid. The amino acids have been found to coordinate through the amine and carboxylate groups. The S-methyl-L-cystene is coordinated not by the sulfur donor atom, but by the nitrogen and oxgen donor atoms, and the L-aspartic and L-glutamic acids are coordinated to the cobalt(Ⅲ) ion via formation of the five-membered glycinate chelate ring. Relatively small optical activity shown by the complexes is due to the chiral center present in the amino acids.

• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.990-996
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• 1994

New ferrocene-based chelate amines, $Fe[C_5H_4CH(Me)NMe_2]_2\;(3), \;Fe[C_5H-3(CH(Me)NMe_2)(PPh_2)-1,2]_2\;(4),\;(C_5H_5)Fe(C_5H_3(CH_2NMe_2)(CH(CN)NMe_2-1,2)\;(6),\;and\;(C_5H_5)Fe(C_5H_3(CH_2NMe_2)(CH(Me)NMe_2-1,2)$ (7) have been prepared. The reaction and the coordination chemistry of 4 and other related compounds (S,R)-(1-N,N-dimethylaminoethyl)-2-dicyclohexylphosphino)ferrocene (CPFA) and 1,1'-bis-(diphenylphosphino)ferrocene (BPPF) with $Rh_2(OAc)_4(MeOH)_2$ were investigated. The reaction of the chiral ligand (S,R)-CPFA forms a complex of the type (${\eta}^1$-(S,R)-CPFA-P)$_2Rh_2(OAc)_4$ (8) in which the ligand is coordinated to both rhodium centers in a monodentate fashion through phosphorus. In contrast, the bisphosphine analogues such as BPPF and 4 afford chelate complexes of the type (${\eta}^2-PP)Rh_2(OAc)_4$ (9 & 10) where both ligands act as a chelate bidentate to a single rhodium atom. All these complexes were characterized by microanalytical and spectroscopic techniques. In one case, the structure of 8 was determined by X-ray crystallography. Crystals are monoclinic, space group C2 (No. 5), with a=26.389 (3), b=12.942 (1), c=11.825 (1) A, ${\beta}$=111.22(1)$^{\circ}$, V=3964.7 (8) $A^3$, Z=4, and $D_{calc}$=1.58 g $cm^{-3}$. Two Rh(II) centers are bridged by four $AcO^-$ groups in the ${\eta}^1$ : ${\eta}^1$ mode across a Rh-Rh single bond, and octahedral coordination at Rh(1) and Rh(1') is completed by axially coordinating (S,R)-CPFA and a briding $AcO^-$, respectively.

• Journal of the Korean Chemical Society
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• v.34 no.4
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• pp.345-351
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• 1990

Optical isomers of DABS-amino acids have been separated in a reversed phae high performance liquid chromatography by adding Cu (Ⅱ)-L-Proline chelate to the mobile phase. The retention behaviors for the DABS-amino acids are discussed in terms of pH of the mobile phase and the concentrations of acetonitrile, Cu (Ⅱ) complex, and buffer. The selectivity of the optical isomers of DABS-amino acids increases with the pH of the mobile, and the concentration of the chelate, but decreases with concentration of the oganic modifier. The concentration of buffer does not affect the optical separation selectivity. A separation mechanism is illustrated by cis and trans formation based on the steric effect of the ligand exchange reaction between DABS-amino acids and the copper chelate.

• Journal of the Korean Chemical Society
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• v.34 no.1
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• pp.76-84
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• 1990

Optical isomers of dansyl amino acids were separated by a chiral mobile phase addition method. Two metha and para isomers of xylenyl-L-proline were prepared and used as the ligands of copper(Ⅱ) chelate to resolve the dansyl amino acids. Their elution behaviors were similar to those obtained from the addition of copper (Ⅱ) benzyl-L-proline chelate. The matrix effect of the mobile phase such as pH, concentration of buffer and compositions of organic solvent acetonitrile affected the optical resolution. The separation mechanism could be explained by a cis-trans effect of the ligand exchange reaction and hydrophobic interaction between the ternary complex and the stationary phase.

• Journal of the Korean Chemical Society
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• v.41 no.9
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• pp.465-470
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• 1997

A chiral pentadentate ligand, 1,9-bis(S)-prolyl-1,9-dioxo-2,5,8-triaza-nonane, (S,S-prochen) which shows the stereospecific reaction was synthesized from the reaction of S-proline and diethylenetriamine (dien). The red-violet $[Co(SS-prodien)H_2O]ClO_4$ was prepared by the oxidation of the aqueous solution dissolving $CoCl_2{\cdot}6H_2O$ and S,S-prodien. Elemental analysis, electronic absorption spectroscopy, and $^{13}C-NMR$ spectroscopy suggest that the geometrical structure of the Co(III) complex to be an ${\alpha}{\beta}$ (ffm) form, where the dien moiety of the ligand chelates the metal center to comprise a facial isomer, and an aqua ligand coordinates a cis site to the secondary nitrogens of the dien. Based upon the CD spectroscopic analysis, it seems that the absolute configuration of the ${\alpha}{\beta}$(ffm)-$[Co(SS-prodien)H_2O]ClO_4$ has the ${\Lambda}$-form.

• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.216-223
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• 1986

Separation of optical isomers of DNS derivatized amino acids by a reversed-phase high-performance liquid chromatography has been studied by adding a complex of an optically active amino acid (L-arginine) with the metal ion (Cu(II), Zn(II), Cd(II), Ni(II)) to the mobile phase. The separations are affected by the concentrations of acetonitrile, chelate and buffer. They are also affected by the pH and the kinds of metal and buffer. A separation mechanism, which is based on steric effect of the ligand exchange reaction for the formation of ternary complexes by the D,L-DNS-amino acids and the chiral additive associated with the stationary phase, is proposed to interpret the elution behaviors of D, L-dansyl-amino acids.