• Journal of Korean Society of Forest Science
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• v.43 no.1
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• pp.14-19
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• 1979

On treatment with sodium hydroxide at $165^{\circ}$ for 1.5~3hr followed by air oxidation. vanillyl alcohol afforded colored materials. $^{13}C$-NMR spectrum of the material did not show any absorptions assigned to the carbons of chromophoric structures, but gave the valuable information on the chemical structures of the condensation products. On the other hand, the colored material specifically labelled by $^{13}C$ at the benzylic position was prepared by alkali treatment of vanillyl alcohol-[carbinol-$^{13}C$] followed by air oxidation, and $^{13}C$-NMR spectra of the material exhibited absorptions at 101.7 and 104.6 ppm due to the carbons of a quinonemethide structure, indicating that the quinomethide unit would be one of the important types of chromophores in which benzylic carbon of vanillyl alcohol was included.

• YAKHAK HOEJI
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• v.32 no.3
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• pp.164-169
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• 1988

$^{13}C$ NMR chemical shifts for 18 ${\alpha}-susbstituted$ toluenes at high dilution in $CCl_4$ solution have been determined. Substituents are as follows: H, Me, Et, n-Pr, iso-Pr, Ph, F, Cl, Br, $NH_2$, NHMe, $NMe_2$, OH, OMe, OCOMe, $CO_2Me$, $CO_2Et$, CN. Those chemical shifts of the methylene carbon of the toluene and the ${\alpha}-carbon$ of the n-butane systems are correlated well. (r=.975, slope=.962)

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.224-227
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• 1991

The "frozen-out" $^{13}C-NMR$ spectrum of cyclooctanone conformer was detected at $-150^{\circ}$ and is reported for the first time. The stable conformation of cyclooctanone deduced by $^{13}C-NMR$ measurements was a unsymmetrical boat-chair conformation.

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.356-360
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• 2007

5,7-Diaryl-3,4,6-trihydronaphthalen-2-ones have been synthesized from 3,5-diaryl-cyclohex-2-en-1- ones and methyl vinyl ketone in the presence of sodium ethoxide. The products were characterized by IR, UV-Visible, 1H-NMR, 13C-NMR and mass spectral techniques. To confirm 1H and 13C signals, HSQC spectrum was recorded and analyzed.

• Korean Journal of Crystallography
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• v.12 no.3
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• pp.141-144
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• 2001

From the reaction of Na[Ga(N₃)₄] with PPh₃, an ionic compound [Ph₃P(OH)]/sup +/[N₃]/sup -/ (1) was isolated. Compound 1 was characterized by spectroscopy (¹H-NMR, /sup 13C{¹H}-NMR, and IR) and X-ray diffraction. Crystallographic data for 1 : orthorhombic space group P2₁2₁2₁, a = 10.491 (4) Å, b=11.603(5)Å, c=13.149(5)Å, Z=4, R(wR₂)=0.0547(0.0978).

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1289-1290
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• 2001

• Applied Biological Chemistry
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• v.38 no.2
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• pp.184-189
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• 1995

(20S)- and (20R)-Ginsenoside $Rh_2$ were prepared from crude ginseng saponin by chemical treatments. The $^1H-$ and $^{13}C-NMR$ signals of these compounds were fully assigned by various NMR techniques such as DEPT, $^1H-^1H$ COSY, HMQC, HMBC and NOESY.

• Analytical Science and Technology
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• v.14 no.1
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• pp.1-7
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• 2001

6,6-Dichlorobicyclo[3, 1, 0]hexane-3carboxylic acid was synthesized by dichlorocarbene addition into 3-cyclopentenecarboxylic acid using BTEA.Cl as phase transfer catalyst. $^1H$ NMR $^{13}C$ NMR data analyst showed that this compound had boat-like conformation and carboxyl group existed as trans form.

• Korean Journal of Crystallography
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• v.12 no.3
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• pp.137-140
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• 2001

Compound PdCl₂(Phc≡N)₂(1) reacted with 2,6-diisopropylaniline to give trans-[Pd(NH₂-C/sub 6/-H₃-2, 6-i-Pr₂)₂Cl₂] (2). Compound 2 was characterized by spectroscopy (¹H-NMR, /sup 13/C-NMR, and IR) and X-ray diffraction. Crystallographic data for 2: monoclinic space group P2₁/n, a=13.532(3) Å, b=5.749(1) Å, c=17.880(4)Å, β=103.84(2)°, Z=2, R(wR₂)=0.0466(0.1226).

• Journal of the Mineralogical Society of Korea
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• v.20 no.2 s.52
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• pp.97-102
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• 2007

NMR experiments with various pulse repetition delay time were carried out for the $^{15}N\;and\;^{13}C$ of a natural gem diamond and synthetic diamonds. The natural gem diamond had a weak $^{13}C$ peak at 34.1ppm when 30 second pulse repetition delay time was applied. Similar but more prominent $^{13}C$ peaks were observed at 34.2 ppm with 0.5 second pulse repetition delay time and at 34.7 ppm with 50 second pulse repetition delay time for the synthetic diamonds. Any meaningful $^{15}N$ peak was not observed for either natural or synthetic diamonds due to extremely low content of the $^{15}N$. Significant relationship was observed between relative spin-lattice relaxation times we estimated and the content of impurities. however, it was not possible to distinguish natural diamond from synthetic diamonds due to very similar characteristics of their $^{13}C$ NMR signals except relative spin-lattice relaxation times.