• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.3009-3014
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• 2014

A palladium-catalyzed C-H arylation reaction of nitroimidazoles and nitropyrazoles was developed using aryl bromides as arene donors. The electron-withdrawing effect of the nitro group allows for direct C-H arylation reactions of the nitro diazoles with high regioselectivity under mild conditions. The new C-H arylation approach is thus complementary to nucleophilic substitution reactions, enabling the preparation of complex nitroazole compounds.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2340-2342
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• 2013

A convenient Rh-catalyzed C-H arylation of imidazo[1,2-a]pyridines with a variety of aryl halides or triflates has been reported. This process afforded a range of biaryl compounds in excellent yields and showed high activity and broad scope.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4167-4170
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• 2011

An inexpensive and efficient catalyst system has been developed for the N-arylation of phenylurea including a variety of aryl halides. This simple protocol uses $Cu_2O$ as the catalyst, microwave assisted, solvent- and ligand-free, $K_3PO_4{\cdot}H_2O$ as the base.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2623-2626
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• 2012

A series of functionalized furans were synthesized by way of a palladium-catalyzed coupling reaction of 2,3,5-trisubstituted furans with aryl chlorides through C-H bond cleavages at C-4 position. The feature of the reaction was facilitative preparation of furan derivatives with good functional group tolerance. All reactions gave the desired products in moderate to good yields in the presences of $BuAd_2P$ and t-BuOK in DMF at $120^{\circ}C$ after 15 h.

• Bulletin of the Korean Chemical Society
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• v.18 no.2
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• pp.218-221
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• 1997

When phenylation of styrene was carried out in the presence of Pd(OAc)2 and PPh3 in benzene, trans-stilbene was obtained in good yield (566%) with high selectivity (98%) under mild condition (55 ℃, 50 psi O2, 20 h). Since trans-stilbene could be produced not only from benzene but also from phenyl group of PPh3 by migration of its phenyl group to Pd, the competitiveness of benzene and the migratory aptitude of aryl group of triarylphosphine toward styrene has been investigated with various phosphines (PR3: P(p-C6H4CH3)3, P(p-C6H4OCH3)3, P(p-C6H4F)3, P(p-C6H4Cl)3, P(C6H5)3, P(C6H11)3, P(OC4H9n)3, P(CH2C6H5)3 and P(C6F5)3). The yield and selectivity toward trans-stilbene are increased as the basicity of the phosphines increases. The composition of arylated olefin from arylphosphine, in turn, increases as the electronegativity of the substituent on the aryl group of arylphosphines increases.

• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.577-581
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• 2010

Spiro[fluorene-9,4'-[4H]indeno[1,2-b]furan] was synthesized, and its $\pi$-conjugation was efficiently elongated using palladium-catalyzed C-H arylation of a furan moiety. The resulting $\pi$-conjugated compounds showed intense fluorescence and extremely high thermal stability.

• Bulletin of the Korean Chemical Society
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• v.6 no.3
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• pp.141-144
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• 1985

N-Arylation reaction of nitrogen-containing heterocycles such as pyridine, nicotinamide and 4,4'-bipyridine was studied. We prepared N-2,4-dinitrophenyl derivatives initially by reacting the above heterocycles with 2,4-dinitrochlorobenzene in ethanol, and then treated the N-2,4-dinitrophenylated heterocycles with various aniline derivatives, $XC_6H_4NH_2$(X = -H, p-$CH_3$, p-$C_2H_5$, p-Cl, p-CN, p-OH, p-$OCH_3$, o-Cl, m-$CH_3$) to yield the corresponding N-arylated compounds in fairly good yields. $H^1$-nmr patterns and peak assignments of the N-arylated products were described.

• Tribology and Lubricants
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• v.32 no.5
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• pp.141-146
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• 2016

The diketopyrrolopyrrole (DPP) pigment is a bicyclic 8-π-electron system containing two lactam units. Typical DPP derivative pigments have melting points of over 350°C and very low solubility in most solvents, and show absorption in the visible region with a molar extinction coefficient of 33,000 dm²mol⁻¹ and strong photoluminescence with maxima in the range 500–600 nm. X-ray structure analyses of DPP show that the whole molecule is almost in one plane. The phenyl rings are twisted out of the heterocyclic plane and the intermolecular hydrogen bonding between neighboring lactam NH and carbonyl units influences the structure of the DPP pigment in the solid state. In this study, mono-N-alkylation and mono-N-arylation were undertaken for Pigment Red 264 or Pigment Orange 73 with alkyl halide and aryl halide, respectively, in the presence of sodium tert-butoxide as a base catalyst to improve the solubility of DPP pigments and their application as CO₂ indicators. The synthetic yield was in the range 11–88%. The indicator dyes are highly soluble in organic solvents and shows pH-dependent absorption (λ_max 501 and 572 nm for the protonated and deprotonated forms, respectively) and emission (λ_max 524 and 605 nm for the protonated and deprotonated forms, respectively) spectra. The mono-N-alkylated and mono-N-arylated DPP pigment was identified by ¹H-NMR (¹H-Nuclear Magnetic Resonance Spectrometer), FT-IR (Fourier Transform Infrared Spectroscopy), and MS (Mass Spectrometry). According to the results of color and hue properties obtained by a color matching analyzer, the synthesized DPP pigment material can be used as a CO₂ indicator.