• 제목/요약/키워드: ${\alpha}$-Halo ester

검색결과 3건 처리시간 0.016초

Reactivity of 7-Dithiocarboxy-imidazo [2,1-b]thiazolium-betnine with Aliphatic Alkylating Agents

  • Song, Jung-Wha;Suh, Myung-Eun;Yoo, Kyung-Ho;Park, Sang-Woo
    • Archives of Pharmacal Research
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    • 제12권1호
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    • pp.17-21
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    • 1989
  • We have reported earlier on the reactivity of 7-dithiocarboxy-3-phenyl-5,6-dihydro imidazo[2,1-b]thiazolium-betaine with several para-substituted phenacyl bromides. In this work reactions of 7-dithiocarboxy-3-phenyl(or methyl)-5,6-dihydro imidazo[2,1-b]thiazolium-betaine with a series of aliphatic alkylating agents of ${\alpha}$ -halo ketone,${\gamma}$-halo koto ester and ${\alpha}$ -halo ester were examined for the similar purpose. In case of ${\alpha}$-halo ketone or ${\gamma}$-halo koto ester such as ${\alpha}$ -chloro acetone or ethyl 4-chloro acetoacetate new biheterocyclic compound was obtained via ring transformation reaction. However, reaction of the betaine with methyl(or ethyl) bromoacetate used as a ${\alpha}$-halo ester, gave, in-stead, S-alkylated quarternary ammonium salt.

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Synthesis and Reaction of Biheterocyclic Thiazolo[3,2-a]pyrimidinium-betaines

  • Yoo, Kyung-Ho;Park ,Sang-Woo
    • Bulletin of the Korean Chemical Society
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    • 제6권5호
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    • pp.272-276
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    • 1985
  • Various new kinds of biheterocyclic betaines were prepared by the reaction of 3-substituted-6,7-dihydro-5H-thiazolo[3,2-a]pyrimidine with electrophiles such as isothioyanates, isocyanates in aprotic solvents, respectively. The biheterocyclic betaines containing methyl group at 3-position of thiazole ring were obtained particularly in good yields at room temperature. These betaines were also reacted with alkyl halide to give quarternary ammonium salts. It was found that these betaines are dissociated in polar organic solvents depending on temperature. And new biheterocyclic compounds via ring transformation were prepared by the reaction of 8-phenyl (thiocarbamoyl)-3-phenyl-6,7-dihydro-5H-thiazolo[3 ,2-a]pyrimidinium-betaine with ${\alpha}$-halo kester ${\alpha}-halo$ ester and ${\gamma}-halo$ keto ester.

중심그룹으로 Bipheny1 ester기를 갖는 새로운 강유전성 액정 (Nes ferroelectric liquid crystal having bipeny1 ester core group)

  • 전영재;이종천;김용배
    • 한국재료학회지
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    • 제4권6호
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    • pp.695-703
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    • 1994
  • 4-(4-Alkyloxybenzoyloxy)-4'-(S)-$\alpha$-halo-alkanoyloxybipeny1계열 액정화합물이 합성되고, 그들의 액정성질이 조사되었다. 합성된 바이페닐 에스터계열 화합물들은 키랄 스메틱 C상 뿐 아니라 키랄 네마틱 및 스메틱 A상을 나타내고, $10^{-7}\textrm{cm}^2$ 이상의 큰 자발분극을 나타내었다.

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