• Proceedings of the Korean Vacuum Society Conference
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• 2008.02a
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• pp.91-91
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• 2008

• Journal of the Korean Society of Industry Convergence
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• v.7 no.1
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• pp.107-113
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• 2004

Several transition metal complexes, [$M(L)X_2$](M=Pd(II), Ni(II); X=CI, Br) are prepared with aminophosphine ligands such as 1,2-bis{(diphenylphosphino)amino}ethane{$Ph_2PNHCH_2CH_2NHPPh_2$}($L_1$), 1,2-bis{(diphenylphosphino)amino}propane{$Ph_2PNHCH(CH_3)CH_2NHPPh_2$}($L_2$), trans-1,2-bis{(diphenylphosphino)amino}cyclohexane{$Ph_2PNHC_6H_{10}NHPPh_2$}($L_3$) and 1,2-bis{(diphenylphosphino)amino}benzene{$Ph_2PNHC_6H_4NHPPh_2$}($L_4$). The properties of these complexes are characterized by optical spectroscopic methods including UV/vis spectroscopy, CD, IR, $^1H$- and $^{31}P-NMR$ together with conductometer and elemental analysis. All complexes are stable under atmospheric environment. Catalytic reactivity for C-C coupling between [$M(L)X_2$] and Grignard reagents(RMgX; R=phenyl, propyl, buthyl) by thermolysis were investigated utilizing GC/mass, $^1H$- and $^{13}C-NMR$. When mol scale is 1:20 at [$Pd(L)Cl_2$] and Grignard reagents, the high catalytic activity for C-C coupling is apparent. The [$M(L)X_2$](X=Cl, Br) complexes which have strong bond at M-P exhibit high yields for C-C coupling reactions. When the central metal ion is Pd(II), the high catalytic activity for C-C coupling is apparent. The complex coordinated with Br shows higher catalytic activity for C-C coupling reactions compared to Cl.

• Korean Journal of Optics and Photonics
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• v.21 no.1
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• pp.6-11
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• 2010

Fluorescent photopolymer film was prepared with composition containing acrylate monomer, binder, a visible light sensitive photo initiator, and fluorescent anthracene polymer. A fluorescent grating pattern was inscribed on the photopolymer film using a 2-beam coupling method. A 514 nm laser was coupled to generate a beam-interference pattern. A highly fluorescent diffractive line pattern was formed on the fluorescent photopolymer within 30 sec. of exposure. The fluorescence intensity was highly enhanced in the patterned area, possibly due to the change in the environment of the fluorescent polymers by the photo-polymerization of monomers. Under a photo-mask, a gap electrode pattern was formed of fluorescent gratings with a sub-micron scale, which was matched well to the calculated value ($2.5\;{\mu}m$ and $0.6\;{\mu}m$) based on the refractive index of the photopolymer and beam incident angle ($3.4^{\circ}$, $15^{\circ}$) to the photopolymer surface.

• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.112-118
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• 2002

Good-to-excellent yields of 2,3-Disubstituted norbornenes (or norbornanes) were obtained using a Pd/Cu catalyzed three-component ternary coupling reaction of aryl halides, norbornadiene (or norbornene), and alkynols in toluene at $100{\circ}C$ in the presence of 5.5 M NaOH as a base and benzyltriethylammonium chloride as a phase transfer catalyst. The results of experiments using various aromatic halides suggest that the ternary coupling reaction is promoted by bromide.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.2911-2915
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• 2011

Efficient synthetic method for the preparation of ethyl 2-aryl-2,3-alkadienoates through Pd-catalyzed selective allenyl cross-coupling reactions of aryl iodides with organoindiums generated in situ from indium and ethyl 4-bromo-2-alkynoate was developed. The cyclization reaction of ethyl 2-aryl-2,3-alkadienoates catalyzed by $AuCl_3$ and AgOTf in the presence of AcOH or TfOH produced various ${\alpha}$-aryl ${\gamma}$-butenolides or ${\gamma}$-substituted ${\alpha}$-aryl ${\gamma}$-butenolides.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.2970-2972
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• 2011

One-pot homo- and cross-coupling reactions of arenediazonium tosylate salts bearing a halogen group have been exploited for the synthesis of biaryls and polyaryls under mild conditions. $Pd(OAc)_2$ has proven to be an efficient catalyst for the successful dual transformation of diazonium salts into p-quaterphenyl (3).

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1965-1968
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• 2005

Extended H$\ddot{u}$ckel molecular calculations have been used to analyze how the magnitude of exchange coupling is influenced by the structural distortions in a series of dinuclear six-coordinate copper(II) complexes bridged by the planar bis-bidentate oxalate anion. Copper(II) ions have distorted octahedral surroundings, one being axially elongated and the other compressed. The magnetic interaction is strong in the former complexes and very weak in the latter. This is interpreted as resulting from a switching of magnetic spin orbitals due to the structural distortions (bond elongation or compression) of the copper sites.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1171-1174
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• 2006

Various off-the-shelf Lewis acids in conjunction with various onium salts are screened for coupling reaction of $CO_2$ with epoxides. Among the tested ones, $VCl_3/n-Bu_4NOAc$, $VCl_3/(n-Bu_4NCl$ or PPNCl), $FeCl_3/ n-Bu_4NOAc$, and $FeCl_3/ n-Bu_4NOAc$are proved to be highly active. Propylene oxide, epichlorohydrin, styrene oxide, and cyclohexene oxide can be converted over 90% yields to the corresponding cyclic carbonates without the use of organic solvents under mild conditions by 0.1-1.0 mol% catalyst charge.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3453-3458
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• 2014

An efficient and practical synthesis of natural moracins, which have diverse range of biological properties including anticancer, antioxidant, and antibacterial activities, has been achieved using $Pd(OAc)_2/P(^tBu)_3-HBF_4$ as a Sonogashira coupling reagent which solved the unreactive problems in case of higher electron density of haloaryl compounds in the reaction. Lowering electron density of halophenol with acetylation and changing Sonogashira coupling reagent from $PdCl_2(PPh_3)_2$ to $Pd(OAc)_2/P(^tBu)_3-HBF_4$ smoothly produce the benzofuran structures in the syntheses of moracins M, N and S. The electron deficient halobenzaldehyde, however, easily forms the benzofuran using original Sonogashira conditions, and utilized for the first synthesis of moracin Y.

• KSBB Journal
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• v.8 no.2
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• pp.110-114
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• 1993

Vinblastine, an anticancer agent was produced by chemical coupling of two different monomeric indole alkaloids, vinblastine and catharanthine in the presence of ferric ion. Vindoline was efficiently extracted from the leaves of vinca (Cafharanthus roseus) by using supercritical carbon dioxide, whereas catharanthine was chemically extracted from the in vitro cultured hairy roots. The extracted crude monomeric precursors were purified by a two-step preparative TLC. The coupling reaction was carried out in the 0.1M glycine buffer(pH 2.0, 5ml) containing 40mM FeC13 with purified vindoline(0.3mg) and catharanthine(0.3mg) at 4$^{\circ}C$. The production yields (weight %) of vinblastine and 3', 4'-anhy-drovinblastine in the products were 23.2 and 26.0, respectively. The produced vinblastine was confirmed by FAB-MS.