• 제목/요약/키워드: ${\alpha},{\beta}$-Unsaturated aldehydes

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Concomitant Addition and Acetalization of α,β-Unsaturated Aldehydes with Diols

  • Jeon, Kyu-Ok;Yu, Ji-Sook;Lee, Chang-Kiu
    • Bulletin of the Korean Chemical Society
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    • 제25권11호
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    • pp.1653-1656
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    • 2004
  • ${\alpha},{\beta}$-Unsaturated aldehydes such as acrolein and crotonaldehyde were reacted with diols in the presence of conc. sulfuric acid to give products of which concomitant addition to C-C double bond and acetalization took place. Boron trifluoride etherate and titanium tetrachloride gave only acetalization products.

${\alpha}$,${\beta}$-不飽和 카르보닐化合物의 還元 아미노화反應 (Reductive Amination of ${\alpha}$,${\beta}$-Unsaturated Carbonyl Compounds with Tetracarbonylhydridoferrate as a Reducing Agent)

  • 김홍석;심상철;심상철
    • 대한화학회지
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    • 제23권2호
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    • pp.99-103
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    • 1979
  • 세개의 ${\alpha}$,${\beta}$-불포화알데히드, 신남알데히드, 크로톤알데히드, 아크로레인을 여러가지 일차 아민 존재하에서 테트라카르보닐철산염으로 환원시켜 상당히 다른 수득률로 N-알킬아민을 합성하였다. 보통, $KHFe(CO)_4$ (22mmole)와 일차아민(22∼44mmole)과 ${\alpha}$,${\beta}$-불포화 알데히드 (22mmole)를 에탄올 용매에 넣고 일산화탄소 분위기하에 실온에서 9∼60시간 자석 젓개로 저어주면 일산화탄소를 천천히 흡수하면서 반응이 진행된다. 생성물은 가스크로마토그래피, 질량분석스펙트럼, 핵자기공명스펙트럼, 적외선스펙트럼 등으로 그 구조를 알았다.

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Selective Reduction by Lithium Bis-or Tris(dialkylamino)-aluminum Hydrides. II. Reaction of Lithium Tris(dibutylamino)-aluminum Hydride with Selected Organic Compounds Containing Representative Functional Groups

  • Cha, Jin-Soon;Lee, Sung-Eun;Lee, Heung-Soo
    • Bulletin of the Korean Chemical Society
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    • 제12권6호
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    • pp.644-649
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    • 1991
  • The approximate rates and stoichiometry of the reaction of excess lithium tris(dibutylamino)aluminum hydride (LT-DBA) with selected organic compounds containing representative functional groups under standardized conditions (tetrahydrofuran, $0^{\circ}C$) were studied in order to characterize the reducing characteristics of the reagent for selective reductions. The reducing ability of LTDBA was also compared with those of the parent lithium aluminum hydride and the alkoxy derivatives. The reagent appears to be much milder than the parent reagent, but stronger than lithium tri-t-butoxyaluminohydride in reducing strength. LTDBA shows a unique reducing characteristics. Thus, the reagent reduces aldehydes, ketones, esters, acid chlorides, epoxides, and amides readily. In addition to that, ${\alpha},{\beta}$-unsaturated aldehyde is reduced to ${\alpha},{\beta}$-unsaturated alcohol. Quinones are reduced to the corresponding diols without evolution of hydrogen. Tertiary amides and aromatic nitriles are converted to aldehydes with a limiting amount of LTDBA. Finally, disulfides and sulfoxides are readily reduced to thiols and sulfides, respectively, without hydrogen evolution.

Long Chain Dicationic Phase Transfer Catalysts in the Condensation Reactions of Aromatic Aldehydes in Water Under Ultrasonic Effect

  • Esen, Ilker;Yolacan, Cigdem;Aydogan, Feray
    • Bulletin of the Korean Chemical Society
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    • 제31권8호
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    • pp.2289-2292
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    • 2010
  • Long chain dicationic ammonium salts were used successfully as phase transfer catalyst in the condensation reactions of aromatic aldehydes in water under ultrasonic irradiation for the first time. The quaternary salt having longer distance between the cation centers was more effective than the mono- and dicationic ones having short chain.

Selective Reduction of Carbonyl Compounds with Diisopinocampheylhaloboranes

  • 차진순;김은주;권오운;김종미
    • Bulletin of the Korean Chemical Society
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    • 제17권1호
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    • pp.50-55
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    • 1996
  • Reaction of carbonyl compounds with diisopinocampheylhaloboranes (Ipc2BX,X=Cl, Br, I) was investigated in detail in order to establish their usefulness as selective reducing agents. The reagents reduced aldehydes and ketones to the corresponding alcohols. The reactivities are in the order of Ipc2BCl Ipc2BBr>Ipc2BI.The reagents also reduced ${\alpha}{\beta}-unsaturated$, aldehydes and ketones to the corresponding allylic alcohols without any detectable 1,4-reduction. Especially, the chloro derivative nicely achieved the selective reduction of aldehyde or ketone groups in the presence of many other functional groups. The most remarkable result of this investigation is that aldehydes and ketones can be selectively reduced in the presence of acid chlorides.

Reaction of Dipyrrolidinoaluminum Hydride in Tetrahydrofuran with Selected Organic Compounds Containing Representative Functional Groups

  • Jin Soon Cha;Oh Oun Kwon;Jong Mi Kim;Jae Cheol Lee
    • Bulletin of the Korean Chemical Society
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    • 제15권8호
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    • pp.644-649
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    • 1994
  • The approximate rates and stoichiometry of reaction of excess dipyrrolinoaluminum hydride (DPAH) with selected organic compounds containing representative functional groups under standardized conditions (tetrahydrofuran, 0, reagent : compound=4 : 1) were examined in order to define the characteristics of the reagent for selective reductions. The reducing ability of DPAH was also compared with that of bis(diethylamino)aluminum hydride (BEAH). The reagent appears to be stronger than BEAH, but weaker than the parent reagent in reducing strength. DPAH shows a unique reducing characteristics. Thus, the reagent reduces aldehydes, ketones, esters, acid chlorides, epoxides, and nitriles readily. In addition to that, ${\alpha},\;{\beta}$-unsaturated aldehyde is reduced to the saturated alcohol. Quinone are reduced cleanly to the corresponding 1,4-reduction products. The examination for possibility of achieving a partial reduction to aldehydes was also performed. Both primary and tertiary aromatic carboxamides are converted to aldehydes with a limiting amount of DPAH. Finally, disulfides and sulfoxides are readily reduced to thiols and sulfides, respectively.