13463-41-7Relevant academic research and scientific papers
Novel synthesis of Bis (N-oxopyridine-2-thionato) zinc (II) using solid precursors
Jo, Won-young,Paek, Seung-Min,Park, Man,Hwang, Seong-Ju,Choy, Jin-Ho
, p. 1071 - 1074 (2006)
Unprecedented solid-transchelation reaction has been established for the synthesis of zinc pyrithione nanoparticles to control particle size within sub-micron range through direct reaction between insoluble layered zinc basic salts and aqueous sodium pyrithione solution at room temperature under ambient atmosphere. The change in crystalline phases upon reaction time clearly reveals that insoluble zinc precursors transform into zinc pyrithione nanoparticles within very short reaction time. Distinguished from usual precipitation reactions, the resulting zinc pyrithione nanoparticles exhibit a narrow size distribution. This unprecedented reaction would leads to a new route for efficient preparation of zinc pyrithione nanoparticles. And it is expected that nanosized zinc pyrithione leads to a great expansion of its application fields.
Synthesis of Bis(trityl)iron(II) and Formation of the Iron(0)-Stabilized o, o-Isomer of Gomberg's Dimer
Hayton, Trevor W.,Touchton, Alexander J.,Wu, Guang
supporting information, p. 4045 - 4049 (2021/12/13)
Treatment of Fe(OAc)2 in THF with 2 equiv of Li(CPh3) at -25 °C results in the formation of [Fe(ν5-CPh3)2] (1) in 22% yield. Complex 1 was characterized by X-ray crystallography, NMR spectroscopy, and 57Fe M?ssbauer spectroscopy and features an ν5 binding
Phosphorus-carbon bond forming reactions of iron tetracarbonyl-coordinated phosphenium ions
King, Ryan C.,Nilewar, Shrikant,Sterenberg, Brian T.
, p. 68 - 74 (2018/11/21)
Abstraction of chloride from [Fe(CO)4(PPh2Cl)] (1) in the presence of PPh3 leads to [Fe(CO)4(PPh2(PPh3))][AlCl4] (2), an iron complex of a phosphine-coordinated phosphenium ion. The PPh3 is readily displaced by ferrocene, leading to an electrophilic aromatic substitution reaction, and formation of [Fe(CO)4{PPh2Fc}] (3) (Fc = ferrocenyl). Alternately, chloride abstraction from 1 in the presence of ferrocene leads directly to 3, via a transient phosphenium ion complex. The transient phosphenium ion complex also reacts with N,N-diethylaniline, indole, and pyrrole to form the respective p-anilinyl, 3-indolyl, and 2-pyrryl phosphine complexes via electrophilic aromatic substitution. Chloride abstraction from [Fe(CO)4(PPhCl2)] in the presence of ferrocene leads to a double substitution reaction, forming [Fe(CO)4{PPhFc2}] (13).
Protonation and electrochemical properties of a bisphosphide diiron hexacarbonyl complex bearing amino groups on the phosphide bridge
Shimamura, Takehiko,Maeno, Yuki,Kubo, Kazuyuki,Kume, Shoko,Greco, Claudio,Mizuta, Tsutomu
, p. 16595 - 16603 (2019/11/19)
A bisphosphide-bridged diiron hexacarbonyl complex 3 with NEt2 groups on the phosphide bridge was synthesized to examine a new proton relay system from the NEt2 group to the bridging hydride between the two iron centers. As a precurs
Iron Catalyzed Hydroformylation of Alkenes under Mild Conditions: Evidence of an Fe(II) Catalyzed Process
Pandey, Swechchha,Raj, K. Vipin,Shinde, Dinesh R.,Vanka, Kumar,Kashyap, Varchaswal,Kurungot, Sreekumar,Vinod,Chikkali, Samir H.
supporting information, p. 4430 - 4439 (2018/04/05)
Earth abundant, first row transition metals offer a cheap and sustainable alternative to the rare and precious metals. However, utilization of first row metals in catalysis requires harsh reaction conditions, suffers from limited activity, and fails to tolerate functional groups. Reported here is a highly efficient iron catalyzed hydroformylation of alkenes under mild conditions. This protocol operates at 10-30 bar syngas pressure below 100 °C, utilizes readily available ligands, and applies to an array of olefins. Thus, the iron precursor [HFe(CO)4]-[Ph3PNPPh3]+ (1) in the presence of triphenyl phosphine catalyzes the hydroformylation of 1-hexene (S2), 1-octene (S1), 1-decene (S3), 1-dodecene (S4), 1-octadecene (S5), trimethoxy(vinyl)silane (S6), trimethyl(vinyl)silane (S7), cardanol (S8), 2,3-dihydrofuran (S9), allyl malonic acid (S10), styrene (S11), 4-methylstyrene (S12), 4-iBu-styrene (S13), 4-tBu-styrene (S14), 4-methoxy styrene (S15), 4-acetoxy styrene (S16), 4-bromo styrene (S17), 4-chloro styrene (S18), 4-vinylbenzonitrile (S19), 4-vinylbenzoic acid (S20), and allyl benzene (S21) to corresponding aldehydes in good to excellent yields. Both electron donating and electron withdrawing substituents could be tolerated and excellent conversions were obtained for S11-S20. Remarkably, the addition of 1 mol % acetic acid promotes the reaction to completion within 16-24 h. Detailed mechanistic investigations revealed in situ formation of an iron-dihydride complex [H2Fe(CO)2(PPh3)2] (A) as an active catalytic species. This finding was further supported by cyclic voltammetry investigations and intermediacy of an Fe(0)-Fe(II) species was established. Combined experimental and computational investigations support the existence of an iron-dihydride as the catalyst resting state, which then follows a Fe(II) based catalytic cycle to produce aldehyde.
Coordination chemistry and oxidative addition of trifluorovinylferrocene derivatives
Heinrich, Darina,Schmolke, Willi,Lentz, Dieter
, p. 105 - 112 (2016/11/11)
Complexes using trifluorovinylferrocene and 1,1′-bis(trifluorovinyl)ferrocene as ligands can be obtained by the reaction with a series of fragments of transition metal complexes. Formation of [Pt(η2-trifluorovinylferrocene)(PPh3)2] (1), [{Pt(PPh3)2}2(η2-1,1′-bis(trifluorovinyl)ferrocene)] (2) and [Pt(η2-1,1′-bis(trifluorovinyl)ferrocene)(PPh3)2] (3) were achieved by ligand substitution in [Pt(η2-CH2?=?CH2)(PPh3)2]. Treatment of eneacarbonyldiiron with trifluorovinylferrocene provided [Fe(CO)4(η2-trifluorovinylferrocene)] (4). Photolytically activated reactions of [MnCp(CO)3] and [MnCp′(CO)3] (Cp′?=?C5H4CH3) afforded [MnCp(CO)2(η2-trifluorovinylferrocene)] (5a) and [MnCp′(CO)2(η2-trifluorovinylferrocene)] (5b) respectively. [Ni(η2-trifluorovinylferrocene)(Cy2P(CH2)2PCy2)] (6) could be obtained by reaction with [Ni(COD)2] and Cy2P(CH2)2PCy2. Furthermore the C[sbnd]F bond activation by oxidative addition in the presence of lithium iodide yielding two isomers of [PtI{η1-difluorovinylferrocene}(PPh3)2] (7a/7b) is presented. Molecular structures of 1, 4 and 7a were elucidated using X-ray single crystal diffraction. The spectroscopic and structural data of these complexes prove the powerful π acceptor abilities of these ligands.
METHOD AND PREPARATION FOR TREATING BALDNESS
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, (2010/08/22)
Various embodiments of the present invention are directed to hair-loss, and include treatments and preparations. Embodiments of the present invention include bactericides, combinations of bactericides and fungicides, combination of bactericides and vasodilators, and combinations of bactericides, fungicides, and vasodilators that are delivered topically to pilosebaceous units within the scalps of persons suffering from hair loss. The treatment kills or controls microbes that disrupt hair growth by changing, inhibiting, or interrupting one or more biological functions of the pilosebaceous units. Certain embodiments of the present invention contain additional active and inactive ingredients, including anti-inflammatory agents, carriers, emulsifiers, antioxidants, and other such substances.
Hydride-containing models for the active site of the nickel-iron hydrogenases
Barton, Bryan E.,Rauchfuss, Thomas B.
, p. 14877 - 14885 (2011/01/05)
The [NiFe]-hydrogenase model complex NiFe(pdt)(dppe)(CO)3 (1) (pdt = 1,3-propanedithiolate) has been efficiently synthesized and found to be robust. This neutral complex sustains protonation to give the first nickel-iron hydride [1H]BF4. One CO ligand in [1H]BF4 is readily substituted by organophosphorus ligands to afford the substituted derivatives [HNiFe(pdt)(dppe)(PR3)(CO)2]BF4, where PR 3 = P(OPh)3 ([2H]BF4); PPh3 ([3H]BF4); PPh2Py ([4H]BF4, where Py = 2-pyridyl). Variable temperature NMR measurements show that the neutral and protonated derivatives are dynamic on the NMR time scale, which partially symmetrizes the phosphine complex. The proposed stereodynamics involve twisting of the Ni(dppe) center, not rotation at the Fe(CO)2(PR3) center. In MeCN solution, 3, which can be prepared by deprotonation of [3H]BF4 with NaOMe, is about 104 stronger base than is 1. X-ray crystallographic analysis of [3H]BF4 revealed a highly unsymmetrical bridging hydride, the Fe-H bond being 0.40 A shorter than the Ni-H distance. Complexes [2H]BF4, [3H]BF4, and [4H]BF4 undergo reductions near -1.46 V vs Fc0/+. For [2H]BF4, this reduction process is reversible, and we assign it as a one-electron process. In the presence of trifluoroacetic acid, proton reduction catalysis coincides with this reductive event. The dependence of i c/ip on the concentration of the acid indicates that H2 evolution entails protonation of a reduced hydride. For [2H] +, [3H]+, and [4H]+, the acid-independent rate constants are 50-75 s-1. For [2H]+ and [3H]+, the overpotentials for H2 evolution are estimated to be 430 mV, whereas the overpotential for the N-protonated pyridinium complex [4H 2]2+ is estimated to be 260 mV. The mechanism of H 2 evolution is proposed to follow an ECEC sequence, where E and C correspond to one-electron reductions and protonations, respectively. On the basis of their values for its pKa and redox potentials, the room temperature values of ΔGH? and ΔGH- are estimated as respectively as 57 and 79 kcal/mol for [1H]+.
Complexes of four-membered group 13 metal(I) N-heterocyclic carbene analogues with metal carbonyl fragments
Jones, Cameron,Stasch, Andreas,Moxey, Graeme J.,Junk, Peter C.,Deacon, Glen B.
, p. 3593 - 3599 (2009/12/02)
The four-membered gallium(I) and. indium(I) heterocycles, [:M(Giso)] (M = Ga or In; Giso = [[N(Ar)I2CN(C6Hu)2)-, Ar = C6H3iPr2-2,6), were treated with a series of transition metal carbonyl
Oxidative addition of thioesters to iron(0): active-site models for Hmd, nature's third hydrogenase
Royer, Aaron M.,Rauchfuss, Thomas B.,Gray, Danielle L.
, p. 3618 - 3620 (2009/12/08)
The thioester Ph2PC6H4-2-C (O ) SPh reacts with Fe2(CO)9 to give [Ph2PC6H 4C(O)]Fe(SPh) (CO)3, a model for the CO-inhibited active site of the enzyme Hmd. T
