• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.189-193
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• 1998

Volatile components were extracted from leaves of two Boxthorn (Lycium chinense M.) cultivars by using simultaneous distillation and extraction, analyzed by gas chromatography-mass spectrometry. Seventy components were identified : 13 acids, 15 alcohols, 18 hydrocarbons, 13 carbonyls, three esters, three ionones, and five others. The principal volatile components (and their peak area percentage) were n-pentanol (11.2～30.2%), phytol (14.5～28.3%), hexadecanoic acid (13.5～17.1%) 2,3-dihydrobenzofuran (1.5～4.2%), benzyl alcohol (1.9-4.8%), phenylacetaldehyde (1.8～3.2%), and octadecadienoic acid (1.7～10.7%). Fresh leaves showed much higher peak area than that of dried leaf in n-pentanol, n-hexanol, cis-2-penten-l-ol, cis-3-hexen-l-ol, benzyl alcohol, and $\beta$-phenylethyl alcohol, while dried leaves showed much higher content than that of fresh leaves in 9-hydroxytheaspran A, octadecanoic acid and octadecadienic acid.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3434-3436
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• 2010

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.927-933
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• 2022

We synthesized (C₁₀H₈N₂H)₂Cr₂O₇, The structure of the product was characterized with FT-IR(infrared) and elemental analysis. The oxidation of benzyl alcohol by (C₁₀H₈N₂H)₂Cr₂O₇ in organic solvents showed that the reactivity increased with the increase of the dielectric constant. The oxidation of alcohols was examined by (C₁₀H₈N₂H)₂Cr₂O₇ in DMF, acetone. As a resuit, (C₁₀H₈N₂H)₂Cr₂O₇ was found as efficicent oxidizing agent that converted benzyl alcohol, allyl alcohol, primary alcohol and secondary alcohols to the corresponding aldehydes or ketones(65%~95%). The selective oxidation of alcohols was also examined by (C₁₀H₈N₂H)₂Cr₂O₇ in DMF, acetone. (C₁₀H₈N₂H)₂Cr₂O₇ was selective oxidizing agent(15%~95%) of benzyl alcohol, allyl alcohol and primary alcohol in the presence of secondary ones. In the presence of DMF solvent with acidic catalyst such as H₂SO₄. (C₁₀H₈N₂H)₂Cr₂O₇ oxidized benzyl alcohol(H) and its derivatives. The Hammett reaction constant(ρ) was -0.69(308K). The observed experimental data were used to rationalize the hydride ion transfer in the rate determining step.

• Journal of the Korean Chemical Society
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• v.56 no.5
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• pp.591-596
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• 2012

Preparation of $AlPMo_{12}O_{40}$ (AlPMo) salts, supported on mesostructured SBA-15 silica, by the reaction deposition strategy causes the formation of isolated AlPMo nanocrystals inside the nanotubular channels. The remarkable characteristic of the SBA-15 structure is that all the cylindrical pores are connected by some small channels. This makes the whole pore system in SBA-15 three-dimensional. We have used 2D hexagonal SBA-15 silicas as hard templates for the nanofabrication of AlPMo salt nanocrystal. The oxidation of alcohols occurs effectively and selectively with $H_2O_2$ as the oxidant. AlPMo salt nanocrystal was used as the catalyst.

• Archives of Pharmacal Research
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• v.28 no.4
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• pp.382-390
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• 2005

chial allylic ethers with a hydroxyl group attached to the $\pi-system$ and chlorosulfonyl isocyanate. The enantioselectivity of the CSI reaction with the chiral allylic and benzylic ethers was examined in various solvents and temperatures. Based on these results, it was proposed that the CSI reaction is a competitive reaction of a $S_{N}i$ (retention) and a $S_{N}1$ mechanism (racemization) according to the stability of the carbocation intermediate. This means that there is a greater proportion of retention with the less stable the carbocation intermediate and vise versa.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.1055-1058
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• 2008

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.179.2-179.2
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• 2003

We have developed the novel one-pot synthetic method for regioselective and stereoselective N-protected amines through the reaction of various ethers with chlorosulfonyl isocyanate (CSI). Also, we found a novel technique to compare directly the stability of carbocations in the solution phase and established the stability order of the various carbocations. And we reported the cleavage of benzyl and p-methoxybenzyl protecting groups of alcohols and phenols in the presence of other functional groups using CSI. (omitted)

• Korean journal of food and cookery science
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• v.17 no.4
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• pp.359-366
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• 2001

This study was performed to analyze the volatile flavor compounds of Eucommia ulmoides leaves as influenced by harvesting time and drying method. Essential oils of fresh, air-dried and freeze-dried leaves of Eucommia ulmoides were extracted by SDE(simultaneous steam distillation and extraction) method using pentane and diethyl ether(1:1), and their volatile flavor compounds were analyzed by GC and GC-MS. Total 51 components, including 10 hydrocarbons, 15 alcohols, 12 aldehydes, 4 ketones, 4 esters and 6 acids were identified in fresh Eucommia ulmoides harvested in July. In fresh samples harvested in September, 15 hydrocarbons, 10 alcohols, 5 aldehydes, 4 ketones, 4 esters and 3 acids were identified. In fresh Eucommia ulmoides, aldehydes(8.25ppm) were the most abundant compounds in July samples and alcohols(18.87ppm) in September ones. Seventy one components, including 21 hydrocarbons, 12 alcohols, 12 aldehydes, 9 ketones, 5 esters, 8 acids and 4 miscellaneous ones were identified in air-dried samples harvested in July. In air-dried samples harvested in September, 10 hydrocarbons, 9 alcohols, 3 aldehydes, 3 ketones, 4 esters, 4 acids and 1 miscellaneous one were identified, and the most abundant compounds in July and September samples were hydrocarbons at 5.06ppm and 15.11ppm, respectively. A total of 41 components, including 13 hydrocarbons, 9 alcohols, 5 aldehydes, 3 ketones, 6 esters and 5 acids were identified in freeze-dried samples harvested in July. Freeze-dried samples harvested in August also contained 41 components but with different types, and the ones of September 26 compounds. In freeze-dried ones, hydrocarbons were the most abundant compounds in July sample and esters in August and September samples.

• Applied Chemistry for Engineering
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• v.26 no.3
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• pp.372-376
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• 2015

6-MQCC (Cr(VI)-6-methylquinoline) complex was synthesized by the reaction of 6-methylquinoline with chromium(VI) trioxide in 6 M HCl. The structure was characterized using IR (Infrared Spectroscopy) and ICP (Inductively Coupled Plasma) analysis. The oxidation of benzyl alcohol using 6-MQCC in various solvents showed that the reactivity increased with the increase of the dielectric constant, in descending order of DMF > acetone > chloroform > cyclohexene. In the presence of DMF solvent with acidic catalyst such as sulfuric acid ($H_2SO_4$), 6-MQCC oxidized benzyl alcohol (H) and its derivatives ($p-OCH_3$, $m-CH_3$, $m-OCH_3$, m-Cl, $m-NO_2$) were effectively oxidized. Electron-donating substituents accelerated the reaction rate, whereas electron acceptor groups retarded the reaction rate. The Hammett reaction constant (${\rho}$) was -0.69 (308 K). The observed experimental data was used to rationalize the fact that the hydride ion transfer occurred at the rate-determining step.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.153-157
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• 2005

4-(Dimethylamino)pyridinium dichromate was synthesized by the reaction of 4-(dimethylamino)pyridine with chromium(VI)trioxide in $H_2O$, and characterized by IR, EA and ICP. The oxidation of benzyl alcohol using 4-(dimethylamino)pyridinium dichromate in various solvents showed that the reactivity increased with the increase of the dielectric constant, in the order: cyclohexen < chloroform < acetone < N,N-dimethylformamide. In the presence of hydrochloric acid(HCl), 4-(dimethylamino)pyridinium dichromate oxidized benzyl alcohol and its derivatives ($p-CH_3$, H, m-Br, $m-NO_2$) smoothly in N,N-dimethylformamide. Electron-donating substituents accelerated the reaction, whereas electron-withdrawing groups retarded the reaction. The Hammett reaction constant($\rho$) was -0.70 at 303K. The observed experimental data have been rationalized as follows: the proton transfer occurs after the prior formation of a chromate ester in the rate-determining step.