• Bulletin of the Korean Chemical Society
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• v.22 no.4
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• pp.375-378
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• 2001

The palladium catalyzed dehalogenative homocoupling of haloarylsulfonates under reductive conditions has proceeded selectively depending on the type of the halogen. Thus, an iodo or a bromo leaving group of haloarylsulfonates was homocoupled to gi ve symmetrical biaryls in good yields with the sulfonate group intact, whereas a chloro leaving group gave no reaction under the conditions used. When the more reactive nickel catalyst was employed instead of the palladium catalyst in the reaction, both dehalogenative and desulfonative homocouplings of haloarylsulfonates occurred regardless of the type of the halogen used.

• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.1925-1926
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• 2009

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1325-1328
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• 2012

• Bulletin of the Korean Chemical Society
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• v.10 no.5
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• pp.475-476
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• 1989

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.657-661
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• 1989

Symmetrical divinyl ketone or divinyl ${\alpha}$-diketone was synthesized in moderately good yields through palladium catalyzed carbonylative homocoupling reaction of vinylmercuric chlorides with carbon monoxide. In order to find out optimum synthetic reaction conditions, we examined the effect of catalysts, bases, solvents and reaction temperature when (E)-styrylmercuric chloride was used as a typical starting material. The best yield of divinyl ${\alpha}$-diketone was obtained in the reaction using 10 mol% of dichlorobis(triphenyl phosphine)palladium (II) as a catalyst, an equivalent of pyridine as a base, 10 mol% of iodine and acetonitrile at 50${\circ}$C under 10 atmospheric pressure of carbon monoxide. The yield of divinyl ${\alpha}$-diketone was decreased under atmospheric pressure of carbon monoxide.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.42-48
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• 2013

Potassium N-heterobiaryltrifluoroborates were successfully prepared via a selective Cu-catalyzed C-N coupling reaction. The $BF_3K$ moiety was well tolerated under the reaction conditions involving CuI and dimethyl-ethylenediamine (DMEDA) in the presence of DMSO. The Pd-catalyzed Suzuki-Miyaura cross couplings of potassium N-heterobiaryltrifluoroborates with bromoarenes were studied to prepare the N-heterotriaryl compounds. Moreover, homocoupling, iodination, and hydroxylation of potassium N-heterobiaryltrifluoroborates provided the corresponding products in high yields.

• Bulletin of the Korean Chemical Society
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• v.7 no.6
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• pp.472-477
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• 1986

The reaction of (E)- or (Z)-1-alkenylmercuric chlorides with acrylic acid derivatives in the presence of 10 mol% of lithium trichloropalladate ($LiPdCl_3$) and an equimolar amount of cupric chloride, as a reoxidant for the palladium, in acetonitrile at room temperature gave the corresponding (E,E)- or (E,Z)-2,4-dienoic acid derivatives stereospecifically in moderate to good yields. The reaction of (E)- or (Z)-3-chloromercuripropenoic acid with olefins under the reaction condintion described above similarly gave good yields of (E,E)- or (Z,E)-2,4-dienoic acids stereospecifically. A side reaction, the homocoupling of alkenylmercuric chlorides, could be minimized by employing the condition described above. However, in the reaction of 3-chloromercuripropenoic acid with olefins under the present condition, the homocoupled side reaction product was not produced.

• Journal of the Korean Chemical Society
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• v.37 no.2
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• pp.228-236
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• 1993

The effect of ferric ion on the reaction of CH_3$MgI with benzylbromide was investigated by determining the product ratio between cross-coupling product, ethylbenzene (A) and homocoupling product, bibenzyl (B) in the presence of ferric ion. When CH_3$MgI prepared with pure magnesium was used, the ratio of A to B was 22 to 78 and with reagent grade magnesium, the ratio became 33 to 67 indicating that metallic impurities in magnesium affect the reaction mechanism to lead less homocoupling product, B. The ratio changes became significant when ferric chloride was added in the reaction mixture in catalytic amounts and the ratio of A to B reached to 80 to 20 at maximum. The reaction in the presence of ferric ion seems to follow mainly an ionic mechanism which involves iron-benzyl bromide ${\pi}$-complex formation. The complex formation is expected to be able to enhance ionic attack of CH_3$MgI on benzyl carbon to give more A.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.522-529
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• 1989

Symmetrical divinyl ketones and divinyl ${\alpha}$-diketones were synthesized in moderately good yields through palladium catalyzed carbonylative homocoupling reaction of vinylic halides. Divinyl ${\alpha}$-diketones were obtained in the highest yield in the presence of 10 atm of carbon monoxide, using 2 mol% ligand added to palladium(II) acetate as catalyst and three equivalents of tributylamine as base in polar solvent at $100^{\circ}C$. Divinyl ketones were synthesized mainly under atmospheric pressure of carbon monoxide. The reaction was also proceeded to several other vinylic halides under the above reaction condition. Thus, divinyl ketones and divinyl ${\alpha}$-diketones were synthesized selectively as expected.