• 제목/요약/키워드: palladium

검색결과 625건 처리시간 0.028초

Palladium-Catalyzed Coupling between Quinolone Moieties and Heteroacyl Stannes - Synthesis of C-7 Heteroacyl Quinolone Derivatives

  • 함원훈;양재권;임태균
    • 한국응용약물학회:학술대회논문집
    • /
    • 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
    • /
    • pp.221-221
    • /
    • 1994
  • The cross-coupling reaction of organo tin reagents with a variety of organic halides, catalyzed by palladium, provides a novel method for generating a carbon-carbon bond. We use this method for antibacterial agents, and synthesis of new quinolone derivatives which have carbon-carbon bond at C-7 position of general quinolone moieties. Aryl tin, quinolone moieties, and palladium catalyst were refluxed in DMF to afford new quinolone derivatives. This palladium catalyzed coupling reactions have capacity for further synthetic elaboration.

  • PDF

Selective Dehalogenative Homocoupling of Haloarylsulfonates by th Use of Palladium Catalyst

  • 이태수;안정호;김진환;배진영
    • Bulletin of the Korean Chemical Society
    • /
    • 제22권4호
    • /
    • pp.375-378
    • /
    • 2001
  • The palladium catalyzed dehalogenative homocoupling of haloarylsulfonates under reductive conditions has proceeded selectively depending on the type of the halogen. Thus, an iodo or a bromo leaving group of haloarylsulfonates was homocoupled to gi ve symmetrical biaryls in good yields with the sulfonate group intact, whereas a chloro leaving group gave no reaction under the conditions used. When the more reactive nickel catalyst was employed instead of the palladium catalyst in the reaction, both dehalogenative and desulfonative homocouplings of haloarylsulfonates occurred regardless of the type of the halogen used.

Synthesis and Mesomorphic Properties of Palladium(II) Complexes Based on 3,4,5-Trialkoxy Benzonitrile Ligands

  • 이명수;유용식;최문근
    • Bulletin of the Korean Chemical Society
    • /
    • 제18권10호
    • /
    • pp.1067-1070
    • /
    • 1997
  • The synthesis and characterization of the nitrile ligands 3,4,5-tridodecyloxy benzonitrile (7) and 3,4,5-trioctadecyloxy benzonitrile (8), and their corresponding palladium(Ⅱ) complexes are described. The nitrile ligands display only a crystalline phase and do not show liquid crystalline behavior, while their corresponding palladium(Ⅱ) complexes dispaly an enantiotropic columnar mesophase. The induction of the columnar mesophase is mainly due to dimerization through the palladium complexation of the half disk-like nitrile ligands giving rise to a trans square planar geometry.

팔라듐 촉매하 결합반응을 이용한 플루비프로펜의 간결한 합성 (Concise Synthesis of Flurbiprofen via Palladium-Catalyzed Cross-Coupling Reactions)

  • 한영택
    • 약학회지
    • /
    • 제59권2호
    • /
    • pp.66-69
    • /
    • 2015
  • A concise synthesis of flurbiprofen, a member of the non-steroidal anti-inflammatory 2-arylpropionic acids, has been accomplished. The key feature of this synthesis involves successive palladium-catalyzed cross coupling reactions. In particular, a 2-arylacylate intermediate, which easily converted to the key 2-arylpropionic acid scaffold, was afforded by a versatile palladium-catalyzed cross coupling reaction between diazopropanate and bisphenylboronic acid. This synthetic procedure would facilitate synthesis of the flurbiprofen and anti-inflammatory 2-arylpropionic acid derivatives.

${\pi}$-알릴리간드를 갖는 산소가교 팔라듐착화합물의 반응성에 관한 연구 (The Study on the Reactivity of Dioxygen Bridged Palladium Complexes Having ${\pi}$-Allyl Ligands)

  • 정평진
    • 대한화학회지
    • /
    • 제30권6호
    • /
    • pp.516-520
    • /
    • 1986
  • 본 연구는 ${\pi}$-알릴리간드를 갖는 산소가교 팔라듐착화합물의 반응성에 관한 것이다. 이 경우에 합성한 산소가교화합물은 산소원으로서 초과산화이온$(O_2^-$)을 사용했다. 합성한 산소가교 팔라듐착화합물의 형태를 검토하기 위하여 벤젠 용매중에서 물, 메탄올 및 아세트산과의 반응을 행하였다. 그 결과 산소가교 팔라듐착화합물은 이들과 반응하여 각각 과산화수소$(H_2O_2)$를 발생하면서 히드록시, 메톡시 및 아세톡시가교 팔라듐착화합물로 변환되었다. 또한 산소가교 팔라듐착화합물은 치환페놀류인 살리실알데히드, 8-히드록시퀴놀린 및 활성메틸렌화합물인 아세틸아세톤, 디메틸말론산과도 반응하여 과산화수소와 단핵팔라듐착화합물을 생성했다. 이것은 착화합물중의 배위산소가 과산화이온$(O_2^{2-})$이며, 강한 염기로서 작용하고 있음을 시사한다.

  • PDF

포스핀류가 배위된 팔라듐 착물에 의한 불포화카르복실산의 카르보닐화 고리반응 (제 3 보). 팔라듐 (0, II)-포스핀계 착물에 의한 불포화카르복실산의 카르보닐화 반응 및 그의 이론적 연구 (Carbonylative Cyclization of Unsaturated Carboxylic Acids by Palladium Complexes with Phosphines [III] Palladium (0, II)-Phosphine Complexes Catalyzed Cabonylation of Unsaturated Carboxylic Acids and It's Theoretical Studies)

  • 도명기;김봉곤;정맹준;송영대;박병각
    • 대한화학회지
    • /
    • 제37권10호
    • /
    • pp.903-909
    • /
    • 1993
  • 팔라듐(0, II)-포스핀계 착물을 촉매로 하여 crotonic acid, methacrylic acid 및 3-butenoic acid 같은 불포화가크복실산의 카르보닐화 고리반응에서 생성가능한 물질의 구조를 확인하고, 그 반응메카니즘을 MM2 와 EHMO 계산에 의해서 추정하였다. 이 반응은 ${\pi}$ -착물을 거쳐 금속 함유 고리화합물을 만든 다음 산화성 첨가반응과 환원성 제거반응이 일어나 진행된다. ${\pi}$ -착물을 안정화시키는 crotonic acid, methacrylic acid 등은 카르보닐화 고리반응이 진행되지 않고, 3-butenoic acid는 무수카르복실산 유도체로서 glutaric anhydride와 3-methylsuccinic anhydride 및 이중결합이 자리옮김된 crotonic acid가 얻어졌다.

  • PDF

염산용액에서 하이드라진에 의한 백금과 팔라듐의 환원석출 (Reductive Precipitation of Platinum and Palladium with Hydrazine in Hydrochloric Acid Solution)

  • 김민석;김병수;유재민;유경근;이재천;김원백
    • 대한금속재료학회지
    • /
    • 제46권4호
    • /
    • pp.233-240
    • /
    • 2008
  • The reductive precipitation of platinum and palladium in hydrochloric acid solution using hydrazine as a reducing agent was investigated. The reductive precipitation ratios of platinum and palladium increased when increasing the stoichiometric ratio for reducing agent, precipitation time, and pH. The precipitation ratio of platinum was much lower than that of palladium. This is the reason the reaction rate of $PtCl{_6}^{2-}{\rightarrow}PtCl{_4}^{2-}$ at the reduction reaction step of $PtCl{_6}^{2-}{\rightarrow}PtCl{_4}^{2-}{\rightarrow}Pt$ is very slow. The purity of platinum precipitated was very affected by metallic impurities, while it was possible to precipitate the high purity palladium since the precipitation rate of palladium was relatively fast. At the pH of 1.3, the precipitation temperature of $25^{\circ}C$, and the addition amounts of the hydrazine of 10 and 1.75 times the stoichiometric ratio, the reductive precipitation ratios of platinum and palladium from their hydrochloric acid solutions containing 2,000 ppm were 98.5% and 99.9% in 30 min, respectively.

Efficient Synthesis of Benzoprostacyclins Using Free-Radical and Palladium-Catalyzed Tandem Alkene Insertion Strategies

  • 이남호
    • Bulletin of the Korean Chemical Society
    • /
    • 제22권8호
    • /
    • pp.857-866
    • /
    • 2001
  • Efficient syntheses of PGI2 analogue 2a and its epimer 3 have been accomplished. Using aryl iodide 6 as the common intermediate, either radical or palladium-assisted tandem alkene insertion strategies have been employed for construction of the benzoprostacyclin framework.

Effects of process variables on morphology of palladium metal deposit in hydrochloric acid medium

  • kim Min-Seuk;Lee Jae-Chun;Kim Won-Back;Jeong Jin-Ki;Nam Chul-Woo
    • 한국지구물리탐사학회:학술대회논문집
    • /
    • 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
    • /
    • pp.642-647
    • /
    • 2003
  • Palladium is widely used for several applications and recovery of palladium from secondary sources becomes increasingly important since palladium is one of maldistributed platinum group metals. Electrochemical recovery of dense palladium metal sheet from Pd leaching solution is a simple and easily controlled method. The surface morphology of the recovered Pd metal was significantly affected by current density and temperature. Dense deposit morphology was in higher stress state regardless of preparation condition under $55^{\circ}C$. Rising temperature up to $70^{\circ}C$ had a stress releasing effect besides densification of Pd deposit.

  • PDF

수소저장-방출싸이클링과 냉간가공과의 관계 (The Relation between Hydrogen Absorption-Desorption Cycling and Cold Work)

  • 정영관;이근진;박규섭;김경훈;김세웅
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2002년도 추계학술대회 논문집
    • /
    • pp.829-832
    • /
    • 2002
  • Deformation of the specimens was investigated on hydrogen absorption-desorption cycling. In order to study this problem, the cold rolled and the annealed palladium thin plate as specimens had been used. By using the electrochemical method, the palladium plate specimens were cyclically hydrogenated in the 0.1mol $H_2SO_4$ electrolyte. As results, it is noted that the thickness of the plate specimens gradually increased in increasing hydrogenation cycles whereas the width and the length decreased. Also, Deformation of the cold rolled palladium specimen was lager than the annealed palladium specimen. And grains in the plate specimen were greatly deformed after hydrogenation cycling. But hydrogen absorption rate scarcely changed.

  • PDF