• 제목/요약/키워드: $\alpha,\beta$-Unsaturated carbonyl compounds

검색결과 22건 처리시간 0.027초

${\alpha}$,${\beta}$-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
    • /
    • 제23권2호
    • /
    • pp.99-103
    • /
    • 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.

  • PDF

Wet SiO2 As a Suitable Media for Fast and Efficient Reduction of Carbonyl Compounds with NaBH3CN under Solvent-Free and Acid-Free Conditions

  • Kouhkan, Mehri;Zeynizadeh, Behzad
    • Bulletin of the Korean Chemical Society
    • /
    • 제31권10호
    • /
    • pp.2961-2966
    • /
    • 2010

  • Reduction of carbonyl compounds such as aldehydes, ketones, $\alpha,\beta$-unsaturated enals and enones, $\alpha$-diketones and acyloins was carried out readily with $NaBH_3CN$ in the presence of wet $SiO_2$ as a neutral media. The reactions were performed at solvent-free conditions in oil bath (70 - $80^{\circ}C$) or under microwave irradiation (240 W) to give the product alcohols in high to excellent yields. Regioselective 1,2-reduction of conjugated carbonyl compounds took place in a perfect selectivity without any side product formation.

  • https://doi.org/10.5012/bkcs.2010.31.10.2961 인용 PDF KSCI

환상 ${\alpha},{\beta}$-불포화 카르보닐 화합물의 선택적 에폭시화 및 환원 (Selective Epoxidation and Reduction of Rigid Cyclic ${\alpha},{\beta}$-Unsaturated Carbonyl Compounds)

  • 마은숙
    • 약학회지
    • /
    • 제49권6호
    • /
    • pp.443-448
    • /
    • 2005

  • Diosgenin (25 (R) - spirost-5-en-3$\beta$ -ol) was oxidized with 2,3-dichloro -5,6-dicyano-1,4-benzoquinone to form 25(R)-1,4,6-spirostatrien-3-one (1) as rigid cyclic $\alpha$,$\beta$-unsaturated carbonyl compound. This compound was reacted with $H_{2}O_{2}$, m-chloroperoxybenzoic acid (mCPBA), NaOCl in the presence with (R,R)- or (S,S)-Jacobsen catalyst, tert-butyl-hydroperoxide (TBHP) in Mo$(CO)_{6}$, and in VO $(acac)_{2}$ catalyst, respectively, 25(R) -1,4,6-spirostatrien -3-one (1) was reduced with $NaBH_{4}$ L-Selectride, $LiAIH_{4}$,$BH_{3}$ $\cdot$$(CH_{3})_{2}S$, Superhydride, Red-Al, and lithium tri-tert-butoxyaluminium hydride. And 25(R)-4,6-spirostadien-3$\beta$-ol (4) was treated with $H_{2}O_{2}$, mCPBA, TBHP in D - (-) - and L-(+)-diisopropyltar-trate and $Ti(OiPr)_{4}$ condition (Sharpless asymmetric epoxidation), TBHP in $Mo(CO)_{6}$, and in $VO(acac)_{2}$ catalyst, respectively.

  • PDF KSCI

A New Synthesis of Triphenylphosphorane Ylide Precursors to α-Keto Amide/Ester and Tricarbonyl Units via Horner-Wadsworth-Emmons Reaction

  • Lee, Kie-Seung
    • Bulletin of the Korean Chemical Society
    • /
    • 제31권10호
    • /
    • pp.2776-2782
    • /
    • 2010

  • Newly developed Horner-Wadsworth-Emmons (HWE) reagents 5 having triphenylphosphorane ylide subunits readily condensed with various carbonyl compounds under mild reaction conditions to afford $\beta,\gamma$-unsaturated $\alpha$-keto triphenylphorane ylides in good to excellent yields, which were hydrogenated over Pd-C (10%)/$H_2$ (1 atm) to give the corresponding $\alpha$-keto triphenylphorane ylides in quasi-quantitative yields. These triphenyphosphorane ylides have been utilized as the precursors to $\alpha$-keto amide/ester and vicinal tricarbonyl units in Wasserman's synthetic protocols, and have previously been prepared only from carboxylic acids/acid chlorides. Our new approaches provide excellent alternatives for the synthesis of triphenylphosphorane ylide precursors to $\alpha$-keto amide/ester and vicinal tricarbonyl units directly from carbonyl compounds in good to excellent yields.

  • https://doi.org/10.5012/bkcs.2010.31.10.2776 인용 PDF KSCI

Selective Reduction of Organic Compounds with Non-Free Hydride Reducing Agents

  • Cha, Jin Soon
    • 통합자연과학논문집
    • /
    • 제1권3호
    • /
    • pp.192-194
    • /
    • 2008

  • A series of non-free hydride reducing systems containing boron or aluminum atom, which possess no metal-hydride bond but an available hydrogen at a branched ${\beta}$-position, has been applied to the selective reduction (chemo--, regio-, and stereoselective reduction) of organic compounds. The systems, comprised of diisopinocampheylborane and diisobutylalane derivatives, exhibited almost perfect selectivities in the reduction of aldehydes and ketones. The characteristics features of this systems leading to a perfect transformation have been depicted in this report, especially in the 1) Reduction of ${\alpha}$,${\beta}$-Unsaturated Carbonyl Compounds to Allylic Alcohols via 1,2-Reduction, 2) Chemoselective Reduction between Structurally Different Carbonyl Compounds, and 3) Stereoselective Reduction of Cyclic Ketones.

  • PDF