• Title/Summary/Keyword: PPh3

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Synthesis and Solution Chemistry of Metal Hydrides from Cationic Rhodium(I) Catalyst Precursors [(L-L)Rh(NBD)]$ClO_4 (L-L=Fe({\eta}^5-C_5H_4PBu^t\;_2)_2,\;Fe{\eta}^5-C_5H_4PPhBu^t)_2)$

  • Tae-Jeong Kim
    • Bulletin of the Korean Chemical Society
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    • v.11 no.2
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    • pp.134-139
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    • 1990
  • The hydrogenation catalyst precursors $[(L-L)Rh(NBD)]ClO_4\;(L-L=Fe({\eta}^5-C_5H_4PBu^t\;_2)_2,\;Fe({\eta}^5-C_5H_4PPhBu^t)_2$; NBD = norbornadiene) react with $H_2(1\;atm,\;30^{\circ}C$, MeOH) to yield $[(L-L)HRh({\mu}-H)_3RhH(L-L)]ClO_4$. These hydrido species are fluxional, and variable temperature NMR studies show the existence of a number of equilibria involving both fluxional and non-fluxional species. The synthesis, solution structures, and fluxional behaviors of these hydrides are described.

Selective Silylation Reaction of Aldehydes with 1,1'-Bis(dimethylsilyl)ferrocene in the Presence of Ni/Pt Catalyst (니켈/백금 촉매에 의한 1,1'-Bis(dimethylsilyl)ferrocene과 Aldehydes의 선택적 Silylation 반응)

  • Kim, Jin-Sik;Choi, Sung-Keun;Lee, Jung-Hyun;Kong, Young-Kun
    • Journal of the Korean Chemical Society
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    • v.51 no.3
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    • pp.232-239
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    • 2007
  • The reaction of 1,1'-bis(dimethylsilyl)ferrocene with various aldehydes in the presence of a catalytic amount of Ni(PEt3)4 lead to the acyclic products by monohydrosilylation. The same reaction in the presence of a catalytic amount of (C2H4)Pt(PPh3)2 leads to the different cyclic six membered ring compound by double silylation. Platinum catalyzed double silylation of 4-cyanobenzaldehyde was generated 5,6-ferrocenylene-1,1,4,4,-tetramethyl-2-oxa-2- cyanophenyl-1,4-disylacyclehexane which was crystallized to have crystal structure.

Novel and Efficient Palladium Complexes with β-Ketoiminate Ligands for the Polymerization of Norbornene

  • Lee, Dong-Hwan;Hwang, Yoon-Joo;Yoon, Jin-San;Choi, Moon-Kun;Lee, Ik-Mo
    • Bulletin of the Korean Chemical Society
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    • v.30 no.3
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    • pp.636-646
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    • 2009
  • A series of the noble palladium complexes containing $\beta$-ketoiminate ligands with internal bases, [Pd(${\eta}^3$-allyl)($\beta$- ketoiminate)], [Pd(Me)($PPh_3$)($\beta$-ketoiminate)] and [Pd(Me)($\beta$-ketoiminate)], have been successfully prepared. Crystallographically determined structures showed that these complexes are distorted square planar and pendant bases of the $\beta$-ketoiminate ligands fail to coordinate to the metal in the first two classes of complexes while bases do coordinate in the 3rd class complexes. These complexes are active towards norbornene polymerization on activation with $H(OEt_2)_2BAr^'_4$ (Ar' = 3,5-bistrifluoromethylphenyl) and modified methylalumioxane (MMAO). MMAO is more efficient for the activation for polymerization. Generally, the polymerization activity increases with the following order; [Pd(allyl)($\beta$-ketoiminate)] < [Pd(Me)($PPh_3$)($\beta$-ketoiminate)] < [Pd(Me)($\beta$-ketoiminate)].

Synthesis and Characterization of Palladium and Platinum Complexes of N,N'-Bis[2'-(diphenylphosphino)phenyl]propane-1,3-diamine. Single-Crystal Structures of $[Pd(Ph_2PC_6H_4NC_3H_6NC_6H_4PPh_2)]$ and $[Pt(Ph_2PC_6H_4NH)(SEt_2)Cl]$

  • 유동원;김은진;강상옥;고재정;이승희
    • Bulletin of the Korean Chemical Society
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    • v.19 no.5
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    • pp.565-568
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    • 1998
  • Novel mononuclear metal complexes with the formula $[M(Ph_2PC_6H_4NC_3H_6NC_6H_4PPh_2)]$ (M=Pd (1); M=Pt (2)) were obtained when N,N'-bis[2'-(diphenylphosphino)phenyl]propane-1,3-diamine, I was mixed with cisdichlorobis(diethylsulfide)palladium and platinum in the presence of NEt3. Two mononuclear metal compounds with the fomula [M(Ph2PC6H4NH)(SEt2)Cl] (M=Pd (3); M=Pt (4)) were synthesized from $M(SEt_2)2Cl_2$ and N-(2'-diphenylphosphinophenyl)-4-amino-1,1,1,5,5, 5-hexafluoro-3-penten-2-one, II by the elimination reaction of hexafluoro pentenone. The X-ray single crystal structures of 1 and 4 are described. X-ray single crystal diffraction analyses reveal that compound 1 is a mononuclear palladium compound with P,N,N,P-coordination mode and 4 is a mononuclear platinum compound with P,N-coordination mode.

Does bilateral uterine artery ligation have negative effects on ovarian reserve markers and ovarian artery blood flow in women with postpartum hemorrhage?

  • Verit, Fatma Ferda;Cetin, Orkun;Keskin, Seda;Akyol, Hurkan;Zebitay, Ali Galip
    • Clinical and Experimental Reproductive Medicine
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    • v.46 no.1
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    • pp.30-35
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    • 2019
  • Objective: Bilateral uterine artery ligation (UAL) is a fertility-preserving procedure used in women experiencing postpartum hemorrhage (PPH). However, the long-term effects of this procedure on ovarian function remain unclear. The aim of this study was to investigate whether bilateral UAL compromised ovarian reserve and ovarian blood supply. Methods: This prospective study included 49 women aged between 21 and 36 years who had undergone a cesarean section for obstetric indications. Of these, 25 underwent uterine bilateral UAL to control intractable atonic PPH. The control group consisted of 24 women who had not undergone bilateral UAL. Standard clinical parameters, the results of color Doppler screening, and ovarian reserve markers were assessed in all participants at 6 months after surgery. The clinical parameters included age, parity, cycle history, body mass index, and previous medication and/or surgery. Color Doppler screening findings included the pulsatility index (PI) and resistance index (RI) for both the uterine and ovarian arteries. The ovarian reserve markers included day 3 follicle-stimulating hormone (FSH) levels, antral follicle count, and $anti-M\ddot{u}llerian$ hormone (AMH) levels. Results: There were no significant differences in the ovarian reserve markers of day 3 FSH levels, antral follicle count, and AMH levels between the study and control groups (p> 0.05 for all). In addition, no significant differences were observed in the PI and RI indices of the uterine and ovarian arteries (p> 0.05 for all). Conclusion: In this study, we showed that bilateral UAL had no negative effects on ovarian reserve or ovarian blood supply, so this treatment should be used as a fertility preservation technique to avoid hysterectomy in patients experiencing PPH.

Oxidation of trans-[FeH(NCS(Me)-S)(dppe)2]I to trans trans-[FeNCS)2(Ph2P(O)CH2CH2P(O)Ph2)2][I3](dppe=PPh2CH2CH2PPh2) (trans-[FeH(NCS(Me)-S)(dppe)2]I 화합물의 trans-[FeNCS)2(Ph2P(O)CH2CH2P(O)Ph2)2][I3]로 산화)

  • Lee, Ji Hwa;Lee, Soon W.
    • Journal of the Korean Chemical Society
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    • v.44 no.4
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    • pp.311-315
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    • 2000
  • The Fe(II)-isothiocyanato complex $trans-[FeH(NCS)(dppe)_2]$ (1) eactedwith iodomethane(Mel) to give methyl isothiocyanide-Fe(n) complex, $trans-FeH(NCS(Me)-S)(dppe)_2]I(2)$. Compound 2 was oxidized to $trans-[Fe(NCS)_2(Ph_2P(O)CH_2CH_2P(O)Ph_2)_2][I_3]$ (3), which was structurally characterized by X-ray diffraction. The molecular structure of 3 showed a bent Fe-NCS group, Crystallographic data for 3: triclinic space group P1,a=11.071(2) A,b=12.054(2)A,c=12.121(1)A, $\alpha=101.02(1){\circ}C{\beta}=95.887(9){\circ}Cr=110.34(1){\circ}C$, $Z=1R(wR_2)=0.0567(0.1294)$.

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Catalytic Reactions of 3-Phenyl-2-propen-1-ol with Perchloratocarbonylbis (triphenylphosphine) rhodium (I)$^\dag$

  • Park, Jeong-Han;Chin, Chong-Shik
    • Bulletin of the Korean Chemical Society
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    • v.8 no.4
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    • pp.324-328
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    • 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.

Electrochemical Properties of Diiron Complexes wish Conjugated Chains (공액 사슬을 갖는 철 화합물의 전기화학적 특성)

  • ;Micheal b. Sponsler
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.6
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    • pp.511-517
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    • 2002
  • The complex 1 $([Cp*Fe(CO)_2]_2-(\mu-CH=CH-CH=CH))$ which have butadiene as a bridge were synthesized from $Cp*(CO)_2FeK$ and cis-3,4-dichlorocyclobutene. The derivatives of complex 1 where one or two carbonyl groups are replaced by phosphine ligands have been prepared by photochemical substitution. The new derivatives $([Cp*Fe(L)_2]_2-(\mu-CH=CH-CH=CH))$ where L = $(Ph_2PCH_2CH_2PPh_2)$ and $([Cp*Fe(CO)(L)]_2-(\mu-CH=CH-CH=CH))$ where L : $PPh_3$ have been characterized from $^^1H-$, $^^13C-$,$^^31P-NMR$ and elemental analysis. Obtained complexes have been studied in electrochemical experiment and UV/VIS-near-IR. The mixed-valence radical cation forms of complex 2, 3 species were found to be delocalized as the Class III. Based on the separation of the waves ($\triangle E$ : 0.470 ~ 0.605 V), the efficiency of electronic communication between two metal centers of cation species leading to stabilization relative to neutral species. The phosphine-substitute complexes (2, 3) displays two reversible oxidation waves and oxidation state of metal centers-dependent color change, electrochromism, was observed from yellow to orange and deep blue in methylene chloride.

Use of Conformational Space Annealing in Molecular Docking

  • Lee, Kyoung-Rim;Czaplewski, Cezary;Kim, Seung-Yeon;Lee, Joo-Young
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2004.11a
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    • pp.221-233
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    • 2004
  • Molecular docking falls into the general category of global optimization problems since its main purpose is to find the most stable complex consisting of a receptor and its ligand. Conformational space annealing (CSA), a powerful global optimization method, is incorporated with the Tinker molecular modeling package to perform molecular docking simulations of six receptor-ligand complexes (3PTB, 1ULB, 2CPP, 1STP, 3CPA and 1PPH) from the Protein Data Bank. In parallel, Monte Carlo with minimization (MCM) method is also incorporated into the Tinker package for comparison. The energy function, consisting of electrostatic interactions, van der Waals interactions and torsional energy terms, is calculated using the AMBER94 all-atom empirical force field. Rigid docking simulations for all six complexes and flexible docking simulations for three complexes (1STP, 3CPA and 1PPH) are carried out using the CSA and the MCM methods. The simulation results show that the docking procedures using the CSA method generally find the most stable complexes as well as the native -like complexes more efficiently and accurately than those using the MCM, demonstrating that CSA is a promising search method for molecular docking problems.

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A Case Report of Acute Primary Pontine Hemorrhage with One-and-a-Half Syndrome, Vertigo, and Paresthesia Treated with Eastern-Western Integrative Medicine (급성 원발성 교뇌 출혈 환자의 하나반증후군, 현기증, 이상감각에 대한 한양방 협진치료 : 증례보고)

  • Se-eun Chun;Ji-eun Lee;Min-gyeol Jeon;Yong-jeen Shin;Sun-ho Shin
    • The Journal of Internal Korean Medicine
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    • v.43 no.6
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    • pp.1289-1300
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    • 2022
  • Background: The purpose of this study was to report the improvement of a patient with one-and-a-half syndrome, vertigo, and paresthesia caused by acute primary pontine hemorrhage (PPH) after a combination treatment of traditional Korean and Western medicine. Case report: A 51-year-old female with one-and-a-half syndrome, vertigo, and paresthesia after PPH was treated with Korean medicine, including herbal medication, acupuncture, and moxibustion, and Western medicine, including medication and rehabilitation therapy during hospitalization. Her progress was evaluated by checking for changes in symptoms with the extraocular muscle (EOM) function test, numeral rating scale (NRS), and follow-up brain computed tomography scans and magnetic resonance imaging (MRI). After 41 days of treatment, the EOM movement was improved, leaving limited abduction of the left eye. The NRS scores for vertigo and paresthesia decreased from 10 to 5 and from 10 to 3, respectively. Improvement was noted in hematoma in MRI, but a new ischemic lesion was also discovered. Conclusion: This case reports the clinical course of one-and-a-half syndrome and suggests that a combined therapy of traditional Korean and Western medicine can be useful for PPH patients with one-and-a-half syndrome, vertigo, and paresthesia. However, studies of larger populations are required.