• Bulletin of the Korean Chemical Society
• /
• 제8권4호
• /
• pp.324-328
• /
• 1987

Reaction of Rh $(ClO_4)(CO)(PPh_3)_2$ (1) with trans-$C_6H_5CH = CHCH_2OH$ (2) produces a new cationic rhodium(Ⅰ) complex, $[Rh(trans-C_6H_5CH = CHCHO)(CO)(PPh_3)_2]ClO_4$ (3) where 2 is coordinated through the oxygen atom but not through the olefinic group. At room temperature under nitrogen, complex 1 catalyzes dehydrogenation, hydrogenolysis, and isomerization of 2 to give $trans-C_6H_5CH$ = CHCHO (4), trans-$C_6H_5CH = CHCH_3$ (5) and $C_6H_5CH_2CH_2CHO$ (6), respectively, and oligomerization of 2 whereas under hydrogen, complex 1 catalyzes hydrogenation of 2 to give $C_6H_5CH_2CH_2CH_2OH$ (7) and hydrogenolysis of 2 to 5 which is further hydrogenated to $C_6H_5CH_2CH_2CH_3$ (8). The dehydrogenation and hydrogenolysis of 2 with 1 suggest an interaction between the rhodium and the oxygen atom of 2, whereas the isomerization and hydrogenation of 2 with 1 indicate an interaction between the rhodium and the olefinic system of 2.

• 대한화학회지
• /
• 제67권6호
• /
• pp.429-440
• /
• 2023

1,1-Dialkyl-2,5-bis(trimethylsilylethynyl)-3,4-diphenylsiloles (R=Et, i-Pr, n-Hex; 3a-c) were prepared and utilized as anode active materials for lithium-ion batteries; 3a was also used as a filler for the solid-state electrolytes (SSE). Siloles 3a-c were prepared by substitution reactions in which the two bromine groups of 1,1-dialkyl-2,5-dibromo-3,4-diphe- nylsiloles, used as precursors, were substituted with trimethylsilylacetylene in the presence of palladium chloride, copper iodide, and triphenylphosphine in diisopropylamine. Among siloles 3a-c, 3a had the best electrochemical properties as an anode material for lithium-ion batteries, including an initial capacity of 758 mAhg^-1 (0.1 A/g), which was reduced to 547 mAhg^-1 and then increased to 1,225 mAhg^-1 at 500 cycles. A 3a-composite polymer electrolyte (3a-CPE) was prepared using silole 3a as an additive at concentrations of 1, 2, 3, and 4 wt.%. The 2 wt.% 3a-CPE composite afforded an excellent ionic conductivity of 1.09 × 10^-3 Scm^-1 at 60℃, indicating that silole 3a has potential applicability as an anode active material for lithium-ion batteries, and can also be used as an additive for the SSE of lithium-ion batteries.

• 한국재료학회지
• /
• 제21권5호
• /
• pp.283-287
• /
• 2011

As the performance of microelectronic devices is improved, the use of copper as a heat dissipation member is increasing due to its good thermal conductivity. The high thermal conductivity of copper, however, leads to difficulties in the joining process. Satisfactory bonding with copper is known to be difficult, especially if high shear and peel strengths are desired. The primary reason is that a copper oxide layer develops rapidly and is weakly attached to the base metal under typical conditions. Thus, when a clean copper substrate is bonded, the initial strength of the joint is high, but upon environmental exposure, an oxide layer may develop, which will reduce the durability of the joint. In this study, an epoxy adhesive formulation was investigated to improve the strength and reliability of a copper to copper joint. Epoxy hardeners such as anhydride, dihydrazide, and dicyandiamide and catalysts such as triphenylphosphine and imidazole were added to an epoxy resin mixture of DGEBA and DGEBF. Differential scanning calorimetry (DSC) analyses revealed that the curing temperatures were dependent on the type of hardener rather than on the catalyst, and higher heat of curing resulted in a higher Tg. The reliability of the copper joint against a high temperature and high humidity environment was found to be the lowest in the case of dihydrazide addition. This is attributed to its high water permeability, which led to the formation of a weak boundary layer of copper oxide. It was also found that dicyandiamide provided the highest initial joint strength and reliability while anhydride yielded intermediate performance between dicyandiamide and dihydrazide.

• 대한화학회지
• /
• 제33권6호
• /
• pp.657-661
• /
• 1989

팔라듐 촉매를 이용한 vinylmercuric chlorides의 CO 첨가반응과 커플링반응을 동시에 진행시키는 CO 첨가 호모커플링반응을 실시하여 대칭 디비닐케톤 또는 디비닐 ${\alpha}$-디케톤을 비교적 좋은 수득율로 얻었다. 디비닐케톤과 디비닐 ${\alpha}$-디케톤의 최적 합성조건을 규명하기 위하여 여러가지 vinylmercuric chlorides의 대표적인 모델로서 (E)-styrylmercuric chloride를 선택하여 촉매의 종류 및 그의 양, 염기, 용매 및 반응온도 등의 조건에 따른 수득율의 변화를 조사하였다. 촉매로 10mol%의 dichlorobis(triphenylphosphine)palladium(II), 염기로 등몰의 Pyridine, 10mol%의 요오드 및 10기압의 일산화탄소 존재하에, acetonitrile 용매 중 50${\circ}$C에서 반응시켜 가장 좋은 수득율로 디비닐 ${\alpha}$-디케톤이 얻어졌으며, 상압의 일산화탄소와의 반응에서는 낮은 수득율로 디비닐 ${\alpha}$-디케톤을 얻었다.

• 폴리머
• /
• 제26권1호
• /
• pp.88-97
• /
• 2002

ortho-cresol novolac형 에폭시/페놀 경화제/triphenylphosphine 수지 시스템의 화학 레올로지 특성에 미치는 아민 실록산 개질제의 영향을 검토하였다. DSC측정으로부터 아민 개질제에 의해 경화 속도와 전환량이 증가하였으며 유리전이온도의 증가도 관찰할 수 있었다. 또한, 저장 탄성률과 손실 탄성률의 교차점으로부터 구한 겔화 시간 및 임계 전환량의 감소를 확인할 수 있었다. 이것으로부터 등온 경화반응이 빠르게 진행됨으로써 점도가 상승하는 것을 알 수 있었다. 전환량의 함수로 얻어진 유리전이온도와 측정된 점도로부터 modified WLF 방정식에서의 $C_1$ 및 $C_2$를 온도 함수로써 나타낼 수 있었으며, 유리전이온도와 $C_1$ 및 $C_2$를 modified WLF 방정식에 적용함으로써 등온 경화반응에 따른 점도변화를 정확히 예측할 수 있었다.

• Bulletin of the Korean Chemical Society
• /
• 제29권7호
• /
• pp.1364-1368
• /
• 2008

The activity of the catalytic system composed of Fe$(acetylacetonate)_3$ (Fe$(acac)_3$), triphenylphosphine, and diethylaluminum chloride for the dimerization of bicyclo[2.2.1]hepta-2,5-diene (2,5-norbornadiene, NBD) to produce hexacyclic endo-endo dimer (hexacyclo[$7.2.1.0^{2,8}.1^{3,7}.1^{5,13}.0^{4,6}$]tetradec-10-ene, Hnn) was significantly enhanced by the presence of $AlCl_3$, especially at the molar ratios of NBD/Fe$(acac)_3$ of 500. XPS analysis of the catalytic systems clearly demonstrates that $AlCl_3$ facilitates the reduction of Fe$(acac)_3$ to form active species, Fe(II) and Fe(0) species. The layer separation was observed when [BMIm]Cl was used along with $AlCl_3$, but catalyst recycle was not very successful.

• 대한화학회지
• /
• 제39권11호
• /
• pp.837-841
• /
• 1995

사염화탄소 속에서 티오프로피온아미드(TPA)와 triethylphosphine oxide(TEPO), triethylphosphine oxide(TPPO), trimethylphosphate(TMP), 그리고 tributyl phosphate(TBP)간의 수소 결합에 대한 열역학적 상수들을 근적외선 분광법을 이용하여 구하였다. TPA의 .nu./.alpha./+amide 2 조합띠는 TPA 단위체 및 수소 결합을 이룬 TPA의 띠로 이루어져 있음이 확인되어 이 띠를 두 개의 Lorentzian-Gaussian 곱함수의 띠로 분해하였다. 온도 및 농도의 변화에 따른 이 조합띠의 변화기로부터 TPA와 TEPO, TPPO, TMP, TBP의 수소 결합 엔탈피는 각각 -21.4, -16.8, -12.8, -12.9kJ/mol이었다. 이 결과는 치환기의 inductive effect 및 steric effect로 설명할 수 있다.

• Bulletin of the Korean Chemical Society
• /
• 제8권3호
• /
• pp.179-183
• /
• 1987

Reactions of $Rh(ClO_4)(CO)(AsPh_3)_2$ with unsaturated nitriles and aldehyde, L, produce a series of new cationic rhodium (I) complexes, $[RhL(CO)(AsPh_3)_2]ClO_4$ (L = $CH_2$ = CHCN, $CH_2$ = C($CH_3$)CN, trans-$CH_3CH$ = CHCN, $CH_2$ = CH$CH_2$CN, trans-$C_6H_5CH$ = CHCN, and trans-$C_6H_5CH$ = CHCHD) where L are coordinated through the nitrogen and oxygen, respectively but not through the ${\pi}$-system of the olefinic group. Dissociation constants for the reaction, $[RhL(CO)(AsPh_3)_2]ClO_4$ $\rightleftharpoons$ $Rh(ClO_4)(CO)(AsPh_3)_2$ + L, have been measured to be $1.20{\times}10^{-4}$ M (L = $CH_2$ = CHCN), $1.05{\times}10^{-4}$ M (L = $CH_2$ = C($CH_3$)CN, $3.26{\times}10^{-5}$ M (L = trans-$CH_3$CH = CHCN) and $6.45{\times}10^{-5}$ M (L = $CH_2$ = CH$CH_2$CN) in chlorobenzene at $25^{\circ}C, and higher than those of triphenylphosphine complexes, $[RhL(CO)(AsPh_3)_2]ClO_4$ where L are the corresponding nitriles that are coordinated through the nitrogen atom. The differences in dissociation constants seem to be predominantly due to the differences in ${\Delta}H$ (not due to the differences in ${\Delta}S$). The weaker Rh-N (unsaturated nitriles) bonding in $AsPh_3$ complexes than in $PPh_3$ complexes (based on ${\Delta}H$ values) suggests that the unsaturated nitriles in 2∼5 are good ${\sigma}$-donor and poor ${\pi}$-acceptor.

• 대한화학회지
• /
• 제34권5호
• /
• pp.452-459
• /
• 1990

일련의 산소 및 황 가교결합의 이핵 몰리브덴(V) 착물, Mo$_2$O$_4$L$_2$, Mo$_2$O$_3$L$_4$, Mo$_2$O$_2$S$_2$L$_2$, 그리고 Mo$_2$OS$_3$L$_2$, L = bis(hydroxyethyl)dithiocarbamate을 합성하였다. 말단과 가교의 산소결합 착물은 수용액에서 (PyH)$_2$MoOCl$_5$ 혹은 MoCl$_5$와 리간드의 반응으로부터 합성되었고, Mo$_2$O$_4^{2+}$핵에서 산소가 황으로 치환된 착물, Mo$_2$O$_2$S$_2$L$_2$은 Mo$_2$OS$_3$L$_2$의 클로로포름 용액에 트리페닐포스핀을 가하므로 합성되었다. 한편, Mo$_2$OS$_3$L$_2$착물은 sodium dithionite 존재하에서 (NH$_4$)$_2$MoS$_4$와 리간드의 수용액으로부터 얻어졌다. 합성한 착물에 대한 원소분석과 ir, uv-vis, nmr, 그리고 mass 스펙트라에 의한 착물의 분광학적 성질을 조사하였다. 또한 디메틸술폭시드 용액에서 이들 착물의 전기화학적 성질을 순환전압-전류법으로 조사하였다.