• Korean Journal of Crystallography
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• v.9 no.2
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• pp.107-113
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• 1998

Ar하에서 trans-FeHCl(dppe)2, 1을 4-chlorobutyronitrile에 녹이면, 착물 trans-[FeH(NCCH2CH2CH2Cl)(dppe)2]Cl, 2가 생성되고, 2는 NaBF4와 반응하여 착물 trans-[FeH(NCCH2CH2CH2Cl)(dppe)2][BF4], 3로 변환된다. 착물 3의 결정학 자료: 단사정계 공간군 P21/c, a=13.540(2) , b=17.058(3) , c=21.853(4) , β=90.15(1)o, Z=4, R(wR2)=0.0524(0.1239).

• Bulletin of the Korean Chemical Society
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• v.9 no.3
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• pp.161-164
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• 1988

Infrared multiphoton decompositions (IRMPD) of $BrCH_2CH_2CH_2CH_2Cl$ were studied by using the pulsed $CO_2$laser. At 0.3 J laser energy the experimentally observed product ratios could be reasonably explained by the RRKM calculation with initial excitation energy of ca. 80 Kcal/mol. The pressure dependence of product yields led us to conclude that the collisional deactivation by the inert gas decreased the yield of low energy dissociation channel more significantly.

• Applied Chemistry for Engineering
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• v.10 no.2
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• pp.196-200
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• 1999

The electrochemical properties of 9-methyl-2,3,6,7-tetramethoxyfluorene have been investigated by cyclic voltammetry in acetonitrile, dichloromethane, trifluoroacetic acid (TFA) and trifluoroacetic acid anhydride (TFAn). The first charge transfer for the compound in $CH_3CN$ appeared to be a quasi-reversible one-electron step. The second oxidation step from cation to dication was irreversible. However, the oxdition of the compound in a mixture of solvents containing $CH_2Cl_2$, TFA and TFAn was reversible for both the first and second charge transfer reactions. Since the electrolytic products display a darkblue color and can be stabilized in the solvent mixture, they may be used as an electrochromic material.

• Bulletin of the Korean Chemical Society
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• v.15 no.7
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• pp.571-576
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• 1994

The photoreactions of $ReH_5(Cyttp)\;(1)\;(Cyttp=PhP(CH_2CH_2CH_2PCy_2)_2)\;with\;CO,\;CO_2\;and\;PMe_3 has been investigated to find the differences in reactivities from those of trismonophosphine analog. Irradiation of 1 under CO, $CO_2$ and excess $PMe_3$ in benzene results in the formation of the complexes, $ReH(CO)_2(Cyttp)\;(2),\;ReH_2({\eta}^2-HCO_2)(Cyttp)\;(3)\;and\;$ReH_3(PMe_3)(Cyttp)$ (4), respectively. The resulting products suggest that photoreactions of $ReH_5(Cyttp)$ proceed by photoextrusion of $H_2$ giving a phototransient species "$ReH_3$(Cyttp)" which can be trapped by CO, $CO_2\;and\;PMe_3$. The structures of 2, 3 and 4 are inferred based on $^1H,\;^{31}P$ NMR and I. R spectroscopy.

• Food Science and Preservation
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• v.22 no.4
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• pp.553-558
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• 2015

The aims of this study was to optimize the extraction conditions of sinigrin from Dolsan leaf mustard. Dolsan leaf mustard (Dolsan-eup, Yeosu-si) harvested during at May 2014 was used for sinigrin extraction. After the extraction of sinigrin using 50% $CH_3CN$, 10% $NH_4Cl$, 60% $CH_2OH$, and 70% $CH_3OH$, the sinigrin content was measured by HPLC analysis. The results showed that sinigrin content was highest with 50% $CH_3CN$ solvent extraction and UV detector sensitivity was greater at 228 nm rather than at 242 nm. The sinigrin concentrations of leaf, stem and root with 50% $CH_3CN$ extraction were 345 ppm, 728 ppm, and 539 ppm, respectively. After extraction of the different parts of Dolsan leaf mustard, The standard retention time by HPLC analysis of sinigrin content was 2.054, 2.032, 2.059, and 2.035 min from the root, stalk, and leaf, respectively. On the other hand, HPLC analysis showed that the leaf extracts contained glucoraphanin, one of glucosinolates. The optimum time and extraction solvent for the sinigrin extraction from Dolsan leaf mustard was found to be 24 hr with 50% $CH_3CN$ solvent. In addition, opotimum UV detector k at 228 nm. These results showed that the optimum extraction conditions for Dolsan leaf mustard were 24 hr extraction with 50% $CH_3CN$ solvent. In addition, the optimum wavelength of UV detector was determined to be 228 nm for sinigrin analysis. Therefore, this study could provide a useful information for sinigrin extraction and its systematic analysis during the storage.

• Bulletin of the Korean Chemical Society
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• v.12 no.3
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• pp.256-257
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• 1991

• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.171-178
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• 1988

The potential energy of adsorbate molecules in the main channel of $K^+$ ion exchanged zeolite L(K-L) was calculated. In K-L which adsorbs three molecules per unit cell, the interaction energies of $H_2O,\;NH_3,\;CH_3NH_2,\;(CH_3)_2NH,\;and\;(CH_3)_3N$ molecules with zeolite lattice are 61.11, 62.31, 65.68, 74.65, and 79.88kJ/mol, respectively. These values are less by 3.7∼12.6kJ/mol than $K^+$ ion affinities with adsorbing molecules. These results may be due to the facts that the electrostatic energies are reduced by the negative charge of the lattice oxygens. The distribution of adsorption sites of $NH_3$ and $CH_3NH_2$ in K-L was investigated by a technique of temperature programmed desorption. The experimental value of desorption energies of $NH_3$ and $CH_3NH_2$ on K-L are in good agreement with the theoritical values. It is concluded that the desorption of $NH_3$ and $CH_3NH_2$ on K-L is the first-order desorption with free readsorption.

• Journal of the Korean Chemical Society
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• v.44 no.4
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• pp.311-315
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• 2000

The Fe(II)-isothiocyanato complex $trans-[FeH(NCS)(dppe)_2]$ (1) eactedwith iodomethane(Mel) to give methyl isothiocyanide-Fe(n) complex, $trans-FeH(NCS(Me)-S)(dppe)_2]I(2)$. Compound 2 was oxidized to $trans-[Fe(NCS)_2(Ph_2P(O)CH_2CH_2P(O)Ph_2)_2][I_3]$ (3), which was structurally characterized by X-ray diffraction. The molecular structure of 3 showed a bent Fe-NCS group, Crystallographic data for 3: triclinic space group P1,a=11.071(2) A,b=12.054(2)A,c=12.121(1)A, $\alpha=101.02(1){\circ}C{\beta}=95.887(9){\circ}Cr=110.34(1){\circ}C$, $Z=1R(wR_2)=0.0567(0.1294)$.

• Bulletin of the Korean Chemical Society
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• v.17 no.7
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• pp.604-607
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• 1996

Semiempirical PM3 MO calculations are applied to estimate both 1-atom (X=S,O,C) and 3-substituent (Y=R, CH2R, SR, CH2SR) effects on the reactions of some 1-atom-replaced and 3-substituted cephem-like β-lactam compounds of thiacephems, oxacephems, and carbacephems. Stabilization energy (SE) of the reaction intermediate for the reaction with a hydroxyl ion can be used to evaluate the facility of a reaction and selected as a chemical reactivity index. With the 1-atom effect only, the SE values obtained imply that thiacephems are generally more reactive than the other two cephem-like molecules and the reactivity order is thiacephems>oxacephems>carbacephems. When it comes to the 3-substituent (Y=R, CH2R, SR, CH2SR) effect, chemical reactivity can be best realized by using a 3-substituted thiacephem molecule capable of giving a resonance-stabilized and electron-rich leaving group after the reaction with a nucleophile. SE values, however, decrease in most cases when an additional intervening ethylene group is present (Y=CH2R, CH2SR). The overall 3-substituent reactivity tendency is SR>CH2SR>R>CH2R.

• Bulletin of the Korean Chemical Society
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• v.22 no.3
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• pp.330-332
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• 2001