• Journal of the Korean Chemical Society
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• v.34 no.2
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• pp.171-178
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• 1990

The rates of the reaction Of $[MoO_2(S_2CNC_4H_8)_2]$ with triphenylphosphine in 1,2-dichloroethane have been by the spectrophotometric method. The increase in absorbance at 514 nm has been interpreted as a result of production of $[Mo_2O_3(S_2CNC_4H_8)_4]$ and the decrease in absorbance then corresponds to the reduction of $[Mo_2O_3(S_2CNC_4H_8)_4]$. The data suggest mechanisms involving the formation of $\mu$-oxo dimer in the first stage and molybdenum(IV) in the second stage.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.477-477
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• 1989

The rates of the reaction of $[MoO_2(S_2CNEt_2)_2]$ with triphenylphosphine in 1,2-dichloroethane have been determined by the spectrophotometric method. The increase in the initial absorbance has been interpreted as a result of the production of $[Mo_2O_3(S_2CNEt_2)_4]$ and the decrease in absorbance then corresponds to the reduction of $[M_2O_3(S_2CNEt_2)_4]$. The data suggest mechanisms involving the enzymatic reaction in the first stage and the decay of intermediate, ${\mu}$-oxo molybdenum (V) dimer in the second stage.

• Journal of the Korean Chemical Society
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• v.23 no.1
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• pp.42-45
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• 1979

The experimental procedures of Beckmann rearrangement mostly involve the use of vigorous conditions such as strongly acidic reagents (conc. HCl, $H_2SO_4$, $PCl_5$, etc.) or elevated temperatures, which frequently cause isomerization of ketooximes prior to rearrangement.We have effected the Beckmann rearrangement on $5{\alpha}$-cholestan-3-one oxime using the carbon tetrachloride-triphenylphosphine reagent under mild, neutral conditions to give 3-aza-A-homo-$5{\alpha}$-cholestan-4-one. This new, mild, facile and rapid general method of Beckmann rearrangement is presented, and compared with the classical (more conventional) Beckmann reagent of polyphosphoric acid.

• Bulletin of the Korean Chemical Society
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• v.24 no.2
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• pp.189-192
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• 2003

The reaction of 4-(2-methylaziridin-1-yl)-3-ureidobenzotrifluorides 4 with triphenylphosphine, carbon tetrachloride, and triethylamine (Appel's condition) led to the corresponding carbodiimides 5, which underwent intramolecular cycloaddition reaction with aziridine under the reaction condition to give the benzimidazolefused heterocycles, 2,3-dihydro-1H-imidazo[1,2-a]benzimidazoles 8 and 12,13-dihydro-5H-benzimidazo[2,3-b] [1,3]benzodiazepines 9.

• Rapid Communication in Photoscience
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• v.2 no.1
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• pp.31-33
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• 2013

The irradiation of electron-beam onto bis-(diphenylphosphino)methane, ethane, propane and butane initiated phenyl-shift from a phosphine to another phosphine atom and subsequent fragmentation resulted in the formation of triphenylphosphine derivative as key intermediate. The mechanism of those processes is speculated.

• Bulletin of the Korean Chemical Society
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• v.15 no.10
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• pp.849-852
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• 1994

The ${\alpha},{\beta}$-enoyl chiral iron complexes, ${\alpha},{\beta}-enoyl-{\eta}^5-(C_5H_5)Fe(CO)(PPh_3)$ (1) were prepared from ${\alpha},{\beta}-enoyl-{\eta}^5-(C_5H_5)Fe(CO)_2$(2) and triphenylphosphine through a photochemical ligand substitution followed by carbonylation.

• Bulletin of the Korean Chemical Society
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• v.17 no.12
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• pp.1132-1135
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• 1996

N-Substituted anilines react with triethanolamine at 180℃ in the presence of a catalytic amount of tris(triphenylphosphine)ruthenium(Ⅱ) chloride to give the corresponding 1-substituted indoles in good to high yields. Similar treatment of the anilines with N-benzyldiethanolamine or triisopropanolamine in place of triethanolamine also affords the indoles in good yields. An intermolecular alkyl group transfer between anilines and alkanolamines is assumed to be the key step of these reactions.

• Bulletin of the Korean Chemical Society
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• v.5 no.5
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• pp.199-201
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• 1984

It has been found that $Rh(ClO_4)(CO)(P(C_6H_5)_3)_2$ catalyzes the hydrogenation and isomerization of soybean oil at room temperature under the atmospheric pressure of hydrogen. The hydrogenation occurs at the olefinic groups to produce saturated groups leaving the ester groups intact, and the isomerization converts $-CH = CH- CH_2-CH = CH-$ units to conjugated dienes and the dienes separated by more than two $-CH_2-$ groups. The rate of the hydrogenation is faster than that of the isomerization.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.294.1-294.1
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• 2016

Transition metal dichalcogenides (TMDs) with two-dimensional layered structure, such as molybdenum disulfide (MoS2) and tungsten diselenide (WSe2), are considered attractive materials for future semiconductor devices due to its relatively superior electrical, optical, and mechanical properties. Their excellent scalability down to a monolayer based on the van der Waals layered structure without surface dangling bonds makes semiconductor devices based on TMD free from short channel effect. In comparison to the widely studied transistor based on MoS2, researchs focusing on WSe2 transistor are still limited. WSe2 is more resistant to oxidation in humid ambient condition and relatively air-stable than sulphides such as MoS2. These properties of WSe2 provide potential to fabricate high-performance filed-effect transistor if outstanding electronic characteristics can be achieved by suitable metal contacts and doping phenomenon. Here, we demonstrate the effect of two different metal contacts (titanium and platinum) in field-effect transistor based on WSe2, which regulate electronic characteristics of device by controlling the effective barreier height of the metal-semiconductor junction. Electronic properties of WSe2 transistor were systematically investigated through monitoring of threshold voltage shift, carrier concentration difference, on-current ratio, and field-effect mobility ratio with two different metal contacts. Additionally, performance of transistor based on WSe2 is further enhanced through reliable and controllable n-type doping method of WSe2 by triphenylphosphine (PPh3), which activates the doping phenomenon by thermal annealing process and adjust the doping level by controlling the doping concentration of PPh3. The doping level is controlled in the non-degenerate regime, where performance parameters of PPh3 doped WSe2 transistor can be optimized.

• Polymer(Korea)
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• v.38 no.3
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• pp.386-390
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• 2014

Efficient stitching methods for the synthesis of tripodal Fr$\acute{e}$chet-type dendrimers containing secondary amine as a connector were elaborated. The synthetic strategy involved Staudinger/aza-Wittig reactions (new click reaction) between tripodal tris(azides) and aldehyde-dendrons in toluene in the presence of triphenylphosphine and followed by the reduction of imine intermediates. The tripodal core (1,3,5-tris-(3-azido-propoxy)-benzene) was chosen to serve as the azide functionalities for dendrimer growth. 1,3,5-Tris-(3-azido-propoxy)-benzene was stitched with the aldehyde-functionalized Fr$\acute{e}$chet-type dendrons via Staudinger/aza-Wittig reactions leading to the formation of the corresponding Fr$\acute{e}$chet-type dendrimers in high yields.