• Title/Summary/Keyword: halides

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Correlation of the Rates of Solvolyses of Benzhydryl Halides Using an Extended Grunwald-Winstein Equation

  • Koh, Han-Joong;Kang, Suk-Jin;Kim, Cheol-Ju
    • Bulletin of the Korean Chemical Society
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    • 제30권2호
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    • pp.378-382
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    • 2009
  • Rates of solvolyses of benzhydryl chloride ($Ph_2$CHCl, 1) and benzhydryl bromide ($Ph_2$CHBr, 2) in ethanol, methanol, and aqueous binary mixtures incorporating ethanol, methanol, 2,2,2-trifluoroethanol (TFE) and acetone are reported. Solvolyses were also carried out in TFE-ethanol mixtures. Application of the extended Grunwald-Winstein equation led to l value of 1.19 (1), 1.29 (2) and m value of 1.00 (1), 0.77 (2), correlation coefficient of 0.965 (1) and 0.970 (2). Sensitivities (l = 1.19 (1), 1.29 (2) and m = 1.00 (1), 0.77 (2)) were similar to those obtained for several previously studied solvolyses, in which an $S_N$2 pathway is proposed for the solvolyses of benzhydryl halides ($Ph_2$CHX, X = Cl or Br).

Rhodium-Catalyzed Highly Regioselective C-H Arylation of Imidazo[1,2-a]pyridines with Aryl Halides and Triflates

  • Liu, Yi;He, Lin;Yin, Guoqiang;Wu, Guojie;Cui, Yingde
    • Bulletin of the Korean Chemical Society
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    • 제34권8호
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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.

Microwave Assisted, Solvent- and Ligand-Free Copper Catalyzed N-Arylation of Phenylurea with Aryl Halides

  • Gavade, Sandip;Shingare, Murlidhar;Mane, Dhananjay
    • Bulletin of the Korean Chemical Society
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    • 제32권12호
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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.

Reactions with Hydrazidoyl Halides (V): Synthesis of Some Amidrazones, Hydrazides, Pyrazoles and Pyrazolo [3, 4-d] pyridazine Derivatives

  • Attaby, Fawzy A.;Zaki, Mayssoune Y.;Abdelhamid, Abdou O.;Ramadan, Nazmy A.
    • Archives of Pharmacal Research
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    • 제13권4호
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    • pp.314-318
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    • 1990
  • 2-Bromo (2'-benzofury)gloxal-2-aryhydrazones I reacted with nucleophiles displacing the bromide. Treatment of I with active methylene compounds yield the pyrazole derivatives VIII-XI. Compounds XII-XIV reacted with hydrazine to give pyrazolo (3, 4-dipyridazine derivative XIV-XIV. The structures of the products were assigned and confirmed on the basis of their elemental analysis and spectral data.

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Kinetic Studies of Reactions of Transition Metal Carbonyl Anion with Allyl Halides

  • Park, Yong-Kwang;Han, In-Sup;Huh, Tae-Sung;Marcetta York Darensbourg
    • Bulletin of the Korean Chemical Society
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    • 제10권2호
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    • pp.134-137
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    • 1989
  • The reaction of $CpMo(CO)_3-M^+(M^+,\;Li^+,\;Na^+,\;K^+,\;PPN^{+a})$ with allyl halide was performed and the details of its counterion effects and solvent effect was investigated under the pseudo-first order conditions. The kinetic data from this reaction were compared with those from the reaction of the same anion with benzyl halides in terms of their inverse counterion effects.

Thermal and Photoinduced Silylallylation Reactions of Organic Halides with 3-Stannyl-2-(silylmethyl)propene

  • 강경태;황성심;곽우영;윤웅찬
    • Bulletin of the Korean Chemical Society
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    • 제20권7호
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    • pp.801-804
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    • 1999
  • Thermal and photoinduced silylallylation reactions of organic halides with 3-stannyl-2-(silylmethyl)propene are explored. Silylallylations occur in moderate to high yields, producing various functionalized allylsilane products in which halide carbon is bonded to the terminal alkenic carbon of allylsilane with the removal of tributyltin group. The reactions, which tolerate functional groups such as carbonyl, ester, nitrile, acetal, and ketal, hold synthetic potential for the construction of functionalized allylsilanes.

MeOH-1,1,2,2-Tetrachloroethane 혼합용매에서 tert-Butyl Halides의 이온화에 미치는 분광용매화변수들의 협동효과 (Cooperative Effects of Solvatochromic Parameters on the Ionizations of tert-Butyl Halides in MeOH-1,1,2,2-Tetrachloroethane Mixtures)

  • 사공열;김시준;주재범
    • 대한화학회지
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    • 제30권3호
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    • pp.265-272
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    • 1986
  • MeOH-1,1,2,2-tetrachloroethane 혼합용매에서 할로겐화삼차부틸(t-BuCl, t-BuBr, t-BuI)의 가메탄올 분해반응을 속도론적으로 연구하였으며, 이온화에 미치는 용매효과를 고찰하기 위하여 6가지 indicater를 이용한 분광용매화비교법을 적용하였다. 이결과 할로겐화삼차부틸의 가메탄올 분해반응에 미치는 용매화의 작용은 용매의 극상-편극성에 기인되는 상호작용이 주된 것이긴 하지만 halide leaving group의 living ability에 미치는 electrophilic assistance와 t-Butyl 양이온쪽에 대한 nucleophilic assistance도 상당히 작용함을 알 수 있다. 특히 hydrogen bonding에 의한 electrophilic assistance는 basicity가 큰 leaving group일수록 커지며 ($I^-), 탄소 중심일수록 커짐을 밝힐 수 있었다. (t-BuCl

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