• 제목/요약/키워드: Triphenylphosphine

검색결과 69건 처리시간 0.029초

1,2-디클로로에탄에서 트리페닐포스핀과 비스(피로리딘디티오카바마토) 디옥소몰리브덴 (Ⅵ) 착물의 산소이동 반응 (Oxygen-atom Transfer of Bis(pyrroridinedithiocarbamato)dioxomolybdenum (Ⅵ) with Triphenylphosphine in 1,2-Dichloroethane)

  • 김창수;송세준
    • 대한화학회지
    • /
    • 제34권2호
    • /
    • pp.171-178
    • /
    • 1990
  • 1,2-디클로로에탄에서 $[MoO_2(S_2CNC_4H_8)_2]$와 트리페닐포스핀 사이의 산소이동 반응에 대한 속도를 분광학적 방법으로 측정하였다. 514nm 부근에서 흡광도가 시간에 따라 증가하였다가 감소하는데, 이것은 반응의 중간단계에서 몰흡광계수가 큰$ [Mo_2O_3(S2_CNC_4H_8)_4]$이 생성되었다가 트리페닐포스핀과 더 이상 반응하면 몰리브덴(IV)가 생성되기 때문이다. 제 1단계에서는 $\mu$-옥소이합체의 생성이, 그리고 제 2단계반응에서는 옥소몰리브덴(IV)가 생성되는 반응과 관련된 메카니즘이 제시된다.

  • PDF

1,2-디글로로에탄에서 트리페닐포스핀과 비스(디에틸디티오카바마토) 디옥소몰리브덴 (VI) 의 산소이동 반응 (Oxygen-atom Transfer of Bis(diethyldithiocarbamato)dioxomolybdenum (VI) with Triphenylphosphine in 1,2-Dichloroethane)

  • 김창수;송세준;오창언
    • 대한화학회지
    • /
    • 제33권5호
    • /
    • pp.477-477
    • /
    • 1989
  • 1,2-디클로로에탄에서 $[MoO_2(S_2CNEt_2)_2]$와 트리페닐포스핀과의 산소이동 반응에 대한 속도를 분광학적인 방법으로 측정하였다. 이 때 시간에 따라 흡광도가 증가하였다가 감소하였는데, 흡광도가 증가되는 단계는 중간체인 $[Mo_2O_3(S_2CNE_t2)_4]$의 생성 때문이고, 흡광도가 감소되는 단계는 이 생성물이 환원되는 과정이다. 제 1단계에서는 효소반응 메카니즘이, 그리고 제 2단계에서는 중간체인 ${\mu}$-옥소몰리브덴(V) 이합체가 감소되는 반응과 관련된 메카니즘이 제시된다.

  • PDF

사염화탄소와 트리페닐포스핀을 사용한 스테로이드 링 A 옥심의 벡크만 자리옮김반응 (Beckmann Rearrangement of Ring A Steroidal Oxime Using the Carbon tetrachloride-triphenylphosphine)

  • 김정균;최순규;박원우;이용태
    • 대한화학회지
    • /
    • 제23권1호
    • /
    • pp.42-45
    • /
    • 1979
  • 벡크만 자리옮김반응의 실험조건은 대부분이 센산 (HCl, $H_2SO_4$, $PCl_5$등)이나, 고온과 같은 격렬한 반응조건을 사용하므로 이러한 조건은 자주 전위보다는 케토옥심의 이성질화를 일으킨다. $5{\alpha}$-cholestan-3-one oxime의 벡크만 전위에 온화하고 중성의 조건인 사염화탄소와 트리페닐포스핀을 사용하여 3-aza-A-homo-5${\alpha}$-cholestan-4-one을 얻었다. 이러한 새롭고, 온화하며 쉽고 빠른 베그만 전위를 소개하고 이러한 방법을 고전적인 벡크만 전위 시약인 폴리인산을 사용한 방법과 비교하였다.

  • PDF

Heterocyclization Reaction of 4-(2-Methylaziridin-1-yl)-3-ureidobenzotrifluorides under Appel's Conditions

  • Cho, Hyun-In;Lee, Kee-Jung
    • Bulletin of the Korean Chemical Society
    • /
    • 제24권2호
    • /
    • pp.189-192
    • /
    • 2003
  • The reaction of 4-(2-methylaziridin-1-yl)-3-ureidobenzotrifluorides 4 with triphenylphosphine, carbon tetrachloride, and triethylamine (Appel's condition) led to the corresponding carbodiimides 5, which underwent intramolecular cycloaddition reaction with aziridine under the reaction condition to give the benzimidazolefused heterocycles, 2,3-dihydro-1H-imidazo[1,2-a]benzimidazoles 8 and 12,13-dihydro-5H-benzimidazo[2,3-b] [1,3]benzodiazepines 9.

Electron-Beam Mediated Rearrangement and Fragmentation of Bis(diphenylphosphino)alkane Derivatives in Gas Phase

  • Jeon, Yea-Sel;Choi, Jeong Chul;Jeong, Young-Sik;Hwang, Kwang-Jin
    • Rapid Communication in Photoscience
    • /
    • 제2권1호
    • /
    • pp.31-33
    • /
    • 2013
  • The irradiation of electron-beam onto bis-(diphenylphosphino)methane, ethane, propane and butane initiated phenyl-shift from a phosphine to another phosphine atom and subsequent fragmentation resulted in the formation of triphenylphosphine derivative as key intermediate. The mechanism of those processes is speculated.

An Efficient Synthesis of$\alpha,\beta-enoyl-\eta^5-(C_5H_5)Fe(CO)(PPh_3)$ Complexes

  • Kwon, Hyok-Boong;Ojima, Iwao
    • Bulletin of the Korean Chemical Society
    • /
    • 제15권10호
    • /
    • pp.849-852
    • /
    • 1994
  • The ${\alpha},{\beta}$-enoyl chiral iron complexes, ${\alpha},{\beta}-enoyl-{\eta}^5-(C_5H_5)Fe(CO)(PPh_3)$ (1) were prepared from ${\alpha},{\beta}-enoyl-{\eta}^5-(C_5H_5)Fe(CO)_2$(2) and triphenylphosphine through a photochemical ligand substitution followed by carbonylation.

Ruthenium Complex-Catalyzed Synthesis of Indoles from N-Substituted Anilines and Alkanolamines

  • 이동엽;조찬식;김주의;윤영주;심상철;송한철
    • Bulletin of the Korean Chemical Society
    • /
    • 제17권12호
    • /
    • pp.1132-1135
    • /
    • 1996
  • N-Substituted anilines react with triethanolamine at 180℃ in the presence of a catalytic amount of tris(triphenylphosphine)ruthenium(Ⅱ) chloride to give the corresponding 1-substituted indoles in good to high yields. Similar treatment of the anilines with N-benzyldiethanolamine or triisopropanolamine in place of triethanolamine also affords the indoles in good yields. An intermolecular alkyl group transfer between anilines and alkanolamines is assumed to be the key step of these reactions.

Hydrogenation and Isomerization of Soybean Oil with Perchloratocarbonylbis-(triphenylphosphine) rhodium (Ⅰ)

  • Jeong, Hyun-Mok;Chin, Chong-Shik
    • Bulletin of the Korean Chemical Society
    • /
    • 제5권5호
    • /
    • pp.199-201
    • /
    • 1984
  • It has been found that $Rh(ClO_4)(CO)(P(C_6H_5)_3)_2$ catalyzes the hydrogenation and isomerization of soybean oil at room temperature under the atmospheric pressure of hydrogen. The hydrogenation occurs at the olefinic groups to produce saturated groups leaving the ester groups intact, and the isomerization converts $-CH = CH- CH_2-CH = CH-$ units to conjugated dienes and the dienes separated by more than two $-CH_2-$ groups. The rate of the hydrogenation is faster than that of the isomerization.

Effects of metal contacts and doping for high-performance field-effect transistor based on tungsten diselenide (WSe2)

  • Jo, Seo-Hyeon;Park, Jin-Hong
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
    • /
    • pp.294.1-294.1
    • /
    • 2016
  • Transition metal dichalcogenides (TMDs) with two-dimensional layered structure, such as molybdenum disulfide (MoS2) and tungsten diselenide (WSe2), are considered attractive materials for future semiconductor devices due to its relatively superior electrical, optical, and mechanical properties. Their excellent scalability down to a monolayer based on the van der Waals layered structure without surface dangling bonds makes semiconductor devices based on TMD free from short channel effect. In comparison to the widely studied transistor based on MoS2, researchs focusing on WSe2 transistor are still limited. WSe2 is more resistant to oxidation in humid ambient condition and relatively air-stable than sulphides such as MoS2. These properties of WSe2 provide potential to fabricate high-performance filed-effect transistor if outstanding electronic characteristics can be achieved by suitable metal contacts and doping phenomenon. Here, we demonstrate the effect of two different metal contacts (titanium and platinum) in field-effect transistor based on WSe2, which regulate electronic characteristics of device by controlling the effective barreier height of the metal-semiconductor junction. Electronic properties of WSe2 transistor were systematically investigated through monitoring of threshold voltage shift, carrier concentration difference, on-current ratio, and field-effect mobility ratio with two different metal contacts. Additionally, performance of transistor based on WSe2 is further enhanced through reliable and controllable n-type doping method of WSe2 by triphenylphosphine (PPh3), which activates the doping phenomenon by thermal annealing process and adjust the doping level by controlling the doping concentration of PPh3. The doping level is controlled in the non-degenerate regime, where performance parameters of PPh3 doped WSe2 transistor can be optimized.

  • PDF

Staudinger/Aza-Wittig 반응에 의한 삼발이 핵을 갖는 Fréchet-type 덴드리머의 합성 (Synthesis of Fréchet-type Dendrimers with Tripodal Core via Staudinger/Aza-Wittig Reactions)

  • 한승철;이재욱;진성호
    • 폴리머
    • /
    • 제38권3호
    • /
    • pp.386-390
    • /
    • 2014
  • 덴드리머의 중심에 삼발이 핵을 갖는 덴드리머의 합성을 위한 효율적인 연결 방법이 개발되었다. 합성전략은 알데히드 덴드론과 아자이드기를 갖는 삼발이 핵 사이의 반응을 톨루엔 용매와 triphenylphosphine 존재하에서 진행하는 새로운 클릭화학(Staudinger/aza-Wittig 반응)을 이용하였다. 덴드리머의 삼발이 핵으로 작용할 수 있는 단위체인 1,3,5-tris-(3-azido-propoxy)-benzene을 합성하였고, 이 화합물의 아자이드기는 덴드리머의 형성에 이용되었다. 1,3,5-Tris-(3-azido-propoxy)-benzene을 이용하여 알데히드 덴드론과 Staudinger/aza-Wittig 반응을 통해 덴드리머를 합성하였으며, 모든 덴드리머는 높은 수득률로 얻어졌다.