• 제목/요약/키워드: alkyne

검색결과 61건 처리시간 0.024초

백금/니켈 촉매를 이용한 1,1'-Bis(dimethylhydrosilyl)ferrocene과 Alkynes, Alkenes의 선택적 Hydrosilyation 반응 (Platinum/Nickel Catalyzed Selective Hydrosilylation of Alkynes and Alkenes with 1,1'-Bis(dimethylhydrosilyl) Ferrocene)

  • 김진식;공영건
    • 대한화학회지
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    • 제54권1호
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    • pp.27-37
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    • 2010
  • 1,1'-Bis(dimethylhydrosilyl)ferrocene과 alkynes의 반응에서($C_2H_4$)Pt$(PPh_3)_2$ 촉매경우는 monohydrosilylation과 dihydrosilylation된 비고리화합물의 혼합물이 주로 생성되었고, Ni$(PEt_3)_4$ 촉매 경우는 monohydrosilylation 생성물 또는 dihydrosilylation 생성물만 얻어지는 선택적인 반응을 하였다. 그리고 Alkenes의 반응에서도 monohydrosilylation된 화합물을 얻었다.

Synthesis of 3,4,5-Trisubstituted Isoxazoles through Gold-Catalyzed Cascade Cyclization-Oxidative Alkynylation and Cyclization-Fluorination of 2-Alkynone O-Methyloximes

  • Song, Doo-Hee;Ryu, Jae-Sang
    • Bulletin of the Korean Chemical Society
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    • 제35권9호
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    • pp.2635-2644
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    • 2014
  • Gold-catalyzed tandem cyclization-oxidative alkynylation and cyclization-fluorination reactions of 2-alkynone O-methyloximes are described. The reactions proceed smoothly at room temperature in the presence of 10 mol % of $(PPh_3)AuNTf_2$, 2.5 equivalents of selectfluor, and 2 equivalents of $K_3PO_4$. 2-Alkynone O-methyloximes undergo intramolecular oxyauration/cyclization and ensuing oxidative cross-coupling and fluorination process to afford the corresponding 3,4,5-trisubstituted isoxazoles in a cascade manner.

Nanocrystalline Copper Oxide(II)-Catalyzed Alkyne-Azide Cycloadditions

  • Song, Young-Jin;Yoo, Chung-Yul;Hong, Jong-Tai;Kim, Seung-Joo;Son, Seung-Uk;Jang, Hye-Young
    • Bulletin of the Korean Chemical Society
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    • 제29권8호
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    • pp.1561-1564
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    • 2008
  • Although the use of Cu(II) salts as catalysts without reductants is limited in the cycloaddition of acetylenes with azides, the catalytic system employing average 10 nm CuO(II) nanoparticles in the absence of reductants shows good catalytic activity to form 1,4-disubstituted 1,2,3-triazoles even in wet THF as well as water. It is also noticeable that CuO(II) nanoparticle catalysts can be recycled with consistent activity. A range of alkynes and azides were subject to the optimized CuO(II) nanoparticle-catalyzed cycloaddition reaction conditions to afford the desired products in good yields.

Cytochrome P-450 2A6 Inhibitor Based on the Indole Moiety

  • Lee, Soo;Lee, Hyang-Yeol
    • 한국응용과학기술학회지
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    • 제29권3호
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    • pp.435-442
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    • 2012
  • The cytochrome P-450 enzymes (CYP 2A6) regulate many endogenous signaling molecules and drugs. Aryl alkynes such as 2-ethynylnaphthalene are important P450 inhibitors which have been extensively studied as medicines or as an effective chemical probes for profiling mouse liver microsomal P-450. Here we have synthesized indole-based novel P450 inhibitor, 5-ethynyl indole 3, and showed that it has successfully inhibited CYP 2A6 by chemical inhibition reaction. By using HPLC equipped with a photo diode array(PDA) detector, all of the peaks derived from the enzymatic reaction have been characterized.

Preparation, Reactions and Catalytic Activities of Water Soluble Iridium-Sulfonated Triphenylphosphine Complex

  • 진종식;장원태;양서균;주광석
    • Bulletin of the Korean Chemical Society
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    • 제18권3호
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    • pp.324-327
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    • 1997
  • Water soluble iridium complex, IrCl(CO)(TPPTS)2·χH2O (1) (TPPTS=m-trisulfonated triphenylphosphine) has been prepared from the reaction of a water soluble complex, IrCl(COD)(TPPTS)2·6H2O (COD=l,5-cyclooctadiene) with CO and unambiguously characterized by electronic absorption, 31P NMR, 13C NMR and IR spectral data. Complex 1 catalyzes the hydration of terminal alkynes to give ketones in aqueous solutions at room temperature. The rate of PhC≡CH hydration dramatically increases with addition of MeOH to the reaction mixture in H2O, which is understood in terms of i) the excellent miscibility between H2O and MeOH and ii) the assumed catalytic hydration pathway involving the initial formation of (alkyne)IrCl(CO)(TPPTS)2.

나노 알루미늄/불소 함유 폴리우레탄 결합제의 합성 및 열적 특성 연구 (Synthesis and Thermal Characteristics of Nano-Aluminum/Fluorinated Polyurethane Binders)

  • ;김진석;권영환
    • 한국추진공학회지
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    • 제20권5호
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    • pp.40-50
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    • 2016
  • 현재 적용되고 있는 에너지화 가소제는 $-NO_2$, $-ONO_2$$-N_3$와 같은 에너지화 활성 그룹을 포함하고 있어서 충격, 쇼크, 열 등 외부환경에 상당히 민감하여 복합화약의 둔감 안정성을 취약하게 한다. 본 연구에서는 민감한 에너지화 활성 그룹이 아니라 근본적으로는 비활성 그룹으로 복합화약의 민감도에는 영향을 미치지 않지만, 복합화약의 반응 시에 테르밋반응에 의해 추가적인 에너지를 발생할 수 있는 불소계 반응성 가소제를 적용한 폴리우레탄 결합제를 클릭반응으로 합성하고 나노 알루미늄과의 테르밋반응에 대한 열적 특성을 고찰하였다.

Palladium Nanoparticles Suspended in an Ionic Liquid as Reusable Catalyst for Alkyne Semihydrogenation

  • Lee, Jin-Kyu;Kim, Dae-Won;Cheong, Min-Serk;Lee, Hyun-Joo;Cho, Byung-Won;Kim, Hoon-Sik;Mukherjee, DebKumar
    • Bulletin of the Korean Chemical Society
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    • 제31권8호
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    • pp.2195-2200
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    • 2010
  • The reaction of $PdCl_2$ dispersed in tetra-n-butylammonium bromide with tributyl amine at $120^{\circ}C$ under argon leads to stable isolable nanometric particles. X-ray diffraction analysis of the material indicated that it is constituted of Pd(0). Transmission electron microscopy analysis of the particles dispersed in acetone shows the mean particle size distribution ($4{\pm}1\;nm$). The isolated palladium nanoparticles can be dispersed in an ionic liquid or in methanol or used in solventless condition for selective hydrogenation of 2-hexyne under mild reaction conditions(0.2 MPa and $20^{\circ}C$). The commercial variety of the Lindlar catalyst was also studied for comparative investigations.

트리플 데카 착물에서부터 Alkynes의 고리화 반응 (A Cyclization of Alkynes from Tripledecker Sandwichcomplexes)

  • 엄재국;박영배;변상인;이혁;곽영우;김태정
    • 대한화학회지
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    • 제35권4호
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    • pp.410-413
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    • 1991
  • 트리플 데카 착물, bis(${\eta}^5$-cyclopentadienyl)-${\mu}$-(${\eta}^6$-2,3-dialkyl-1,4-dimethyl-1,4-dibora-2,5-cyclohexadiene)dicobalt 1을 합성하고, 이것을 출발물질로 하여 여기에 3-hexyne을 과량으로 반응시켰더니 두 종류의 sandwich 착물인 cyclopentadienyl(${\eta}^6$-2,3-dialkyl-1,4-dimethyl-1,4-dibora-2,5-cyclohexadiene)cobalt 2와 cyclopentadienyl(${\eta}^6$-hexaethyl benzene)cobalt 3가 분리되었다. 착물 3은 실온에서 정제하는 동안 분해하여 3-hexyne의 고리화 반응 생성물인 hexaethyl benzene이 생성되었음을 확인하였다.

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Theoretical Study on the Mechanism of the Addition Reaction between Cyclopropenylidene and Formaldehyde

  • Tan, Xiaojun;Li, Zhen;Sun, Qiao;Li, Ping;Wang, Weihua
    • Bulletin of the Korean Chemical Society
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    • 제33권6호
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    • pp.1934-1938
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    • 2012
  • The reaction mechanism between cyclopropenylidene and formaldehyde has been systematically investigated employing the MP2/6-311+$G^*$ level of theory to better understand the cyclopropenylidene reactivity with carbonyl compound. Geometry optimization, vibrational analysis, and energy property for the involved stationary points on the potential energy surface have been calculated. Energies of all the species are further corrected by the CCSD(T)/6-311+$G^*$ single-point calculations. It was found that one important reaction intermediate (INTa) has been located firstly $via$ a transition state (TSa). After that, the common intermediate (INTb) for the two pathways (1) and (2) has been formed $via$ TSb. At last, two different products possessing three- and four-membered ring characters have been obtained through two possible reaction pathways. In the reaction pathway (1), a three-membered ring alkyne compound has been obtained. As for the reaction pathway (2), it is the formation of the four-membered ring conjugated diene compound. The energy barrier of the ratedetermining step of pathway (1) is lower than that of the pathway (2), and the ultima product of pathway (2) is more stable than that of the pathway (1).