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81.
A. S. Rozenberg E. I. Aleksandrova G. I. Dzhardimalieva A. N. Titkov A. D. Pomogailo 《Russian Chemical Bulletin》1993,42(10):1666-1672
The thermal decomposition of iron (III) acrylate, [Fe3O(CH2=CHCOO)6 · 3H2O]OH (FeAcr), a monomer with a complex cluster cation, has been studied at 200–370 °C. Thermal transformations of FeAcr occur
in two temperature regions. The rates of gas evolution in the low temperature region (200–300 °C) and the high temperature
region (300–370 °C) are described by first-order equations withk=4.2 · 1021exp[−59000/(RT)] s−1 andk=1.3 · 106exp[−30500/(RT)] s−1, respectively. A study of the qualitative and quantitative composition of the products of FeAcr thermolysis was carried out.
The thermal transformation of FeAcr is a complex process of dehydration, degradation, and polymerization in the solid phase
followed by decarboxylation of the metal-carboxyl groups of the polymer.
for part 33 see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1743–1750, October, 1993. 相似文献
82.
F.?I.?DanilovEmail author V.?S.?Protsenko A.?V.?Ubiikon' 《Russian Journal of Electrochemistry》2005,41(12):1282-1289
The kinetics of a multistep reaction of electrodeposition of iron out of aqueous citrate-containing solutions of trivalent iron is investigated. It is shown that concentrations of major solution components affect the partial current density of discharge of ions of divalent iron. It is established that the deposition of metallic iron occurs as a result of discharge of intermediates, which are hydroxy complexes of divalent iron. Kinetic parameters and mechanism of the reaction of discharge of complexes [FeOH]+ to a metallic state are determined. It is mentioned that the formation of poorly soluble hydroxy compounds of trivalent iron in a near-electrode layer leads to a decrease in the iron deposition current. 相似文献
83.
Tyson L ChasseJoshua C Yohannan Namjin KimQun Li Zemin LiChristopher B Gorman 《Tetrahedron》2003,59(22):3853-3861
Examples of new dendrimers are presented. In the first, the effect on electron transfer rate attenuation is investigated for two dendrimer isomers that differ only in the linkage (ortho- versus meta-linked) of the phenyl ether units within one generation of the structure. Second, the effect of encapsulation on electrochemical and luminescence behavior of a new type of rhenium selenide cluster core dendrimer is illustrated. 相似文献
84.
H. Honda A. Oshima H. Hinode M. Wakihara 《Journal of Thermal Analysis and Calorimetry》1992,38(8):1939-1945
Enthalpy increment HT-H289K measurements have been made on iron Chevrel phase sulphide Fe2Mo6S7.8, in the temperature range 300 to 500 K by the drop method using a hightemperature Calvet-type twin calorimeter. The first-order phase transition of this sulphide from a triclinic (low-temperature phase) to a rhombohedral (high-temperature phase) occurred at 375 K, and the enthalpy was evaluated to be 6.0 kJ/mol. The heat capacities of iron Chevrel phase sulphide Fe2Mo6S7.8 were also calculated before and after the phase transition.
Zusammenfassung Nach der Tropfenmethode wurden mittels eines Hochtemperaturdoppelkalorimeters vom Typ Calvet im Temperaturbereich 300–500 K an Fe2Mo6S7.8Messungen der Enthalpieinkremente HT-H298K durchgeführt. Die Phasenumwandlung erster Ordnung bei diesem Sulfid von der triklinen (Niedertemperaturphase) in die rhomboedrische (Hoch-temperaturphase) erfolgt bei 375 K und die Enthalpie erhielt man mit einem Wert von 6.0 kJ/mol. Die Wärmekapazitäten für Fe2Mo6S7.8 wurden sowohl vor als auch nach der Phasenumwandlung berechnet.相似文献
85.
The reactions of the cationic, diiron-bridging carbyne complexes [Fe(2)(mu-CAr)(CO)(4)(eta(8)-C(8)H(8))]BF(4) (1, Ar=C(6)H(5); 2, Ar=p-CH(3)C(6)H(4); 3, Ar=p-CF(3)C(6)H(4)) with LiN(C(6)H(5))(2) in THF at low temperature gave novel N-nucleophilic-addition products, namely, the neutral, diiron-bridging carbyne complexes [Fe(2)(mu-CAr)(CO)(4)(eta(7)-C(8)H(8)N(C(6)H(5))(2))] (4, Ar=C(6)H(5); 5, Ar=p-CH(3)C(6)H(4); 6, Ar=p-CF(3)C(6)H(4))). Cationic bridging carbyne complexes 1-3 react with (C(2)H(5))(2)NH, (iC(3)H(7))(2)NH, and (C(6)H(11))(2)NH under the same conditions with ring cleavage of the COT ligand to produce the novel diiron-bridging carbene inner salts [Fe(2)[mu-C(Ar)C(8)H(8)NR(2)](CO)(4)] (7, Ar=C(6)H(5), R=C(2)H(5); 8, Ar=p-CH(3)C(6)H(4), R=C(2)H(5); 9, Ar=p-CF(3)C(6)H(4), R=C(2)H(5); 10, Ar=C(6)H(5), R=iC(3)H(7); 11, Ar=p-CH(3)C(6)H(4), R=iC(3)H(7); 12, Ar=p-CF(3)C(6)H(4), R=iC(3)H(7); 13, Ar=C(6)H(5), R=C(6)H(11); 14, Ar=p-CH(3)C(6)H(4), R=C(6)H(11), 15, Ar=p-CF(3)C(6)H(4), R=C(6)H(11)). Piperidine reacts similarly with cationic carbyne complex 3 to afford the corresponding bridging carbene inner salt [Fe(2)[mu-C(Ar)C(8)H(8)N(CH(2))(5)](CO)(4)] (16). Compound 9 was transformed into a new diiron-bridging carbene inner salt 17, the trans isomer of 9, by heating in benzene. Unexpectedly, the reaction of C(6)H(5)NH(2) with 2 gave a novel COT iron-carbene complex [Fe(2)[=C(C(6)H(4)CH(3)-p)NHC(6)H(5)](mu-CO)(CO)(3)(eta(8)-C(8)H(8))] (18). However, the analogous reactions of 2-naphthylamine with 2 and of p-CF(3)C(6)H(4)NH(2) with 3 produce novel chelated iron-carbene complexes [Fe(2)[=C(C(6)H(4)CH(3)-p)NC(10)H(7)](CO)(4)(eta(2):eta(3):eta(2)-C(8)H(9))] (19) and [Fe(2)[=C(C(6)H(4)CF(3)-p)NC(6)H(4)CF(3)-p](CO)(4)(eta(2):eta(3):eta(2)-C(8)H(9))] (20), respectively. Compound 18 can also be transformed into the analogous chelated iron-carbene complex [Fe(2)[=C(C(6)H(4)CH(3)-p)NC(6)H(5)](CO)(4)(eta(2):eta(3):eta(2)-C(8)H(9))] (21). The structures of complexes 6, 9, 15, 17, 18, and 21 have been established by X-ray diffraction studies. 相似文献
86.
New Oxides with the “Butterfly-Motive”: Rb6[Fe2O5] and K6[Fe2O5] Rb6[Fe2O5] and K6[Fe2O5] were obtained for the first time by annealing intimate mixtures of “Rb6CdO4” with CdO (molar ratio 1 : 1.1) and KO0.48 with CdO (molar ratio 5.9 : 1) respectively in closed Fe-cylinders. Determination and refinement of the crystalstructure confirms the space group C2/m (four-circle-diffractometer data). Rb6[Fe2O5]: Ag Kα , 720 out of 1220 Io(hkl), R = 9.68%, Rw = 6.09%; a = 718.9pm, b = 1183.1 pm, c = 695.4pm, β = 95.05°, Z = 2; K6[Fe2O5]: MoKα , 1214 Out of 12141o(hkl), R = 3.20070, Rw = 2.48%, a = 691.21 pm, b = 1142.78pm, c = 665.50pm, β = 93.82°, Z = 2. The binuclear unit [O2FeOFeO2]6? already known to be planar with oxoferrates(II) now was observed to be angular here and closely related to Na6[Be2O5]. 相似文献
87.
Shariff?E.?KabirEmail author M.?Arzu?Miah M.?Abdur?Rahim Sonia?Sultana G.?M.?Golzar?Hossain Ebbe?Nordlander Edward?Rosenberg 《Journal of Cluster Science》2005,16(1):93-110
Treatment of Ru3(CO)12 with dpphSe2 (dpph = 1,6-bis(diphenylphosphino)hexane) in refluxing toluene in the presence of Me3NO afforded two new compounds, Ru3(CO)7(-CO)(3-Se)(-dpph) (1) and Ru3(CO)7(3-Se)2(-dpph) (2). A similar reaction of Ru3(CO)12 with dpppeSe2 (dpppe = 1,5-bis(diphenylphosphino)pentane) gave exclusively Ru3(CO)7(3-Se)2(-dpppe) (3). Treatment of Ru3(CO)12 with dpphS2 and dpppeS2 at 110°C in the presence of Me3NO afforded Ru3(CO)7(3-S)2(-dpph) (4) and Ru3(CO)7(3-S)2(-dpppe) (5), respectively. Reactions of Fe3(CO)12 with dpphSe2 and dpppeSe2, under identical conditions, afforded Fe3(CO)7(3-Se)2(-dpph) (6) and Fe3(CO)7(3-Se)2(-dpppe) (7), respectively. Compounds 1–7 were characterized spectroscopically and the molecular structures of compounds 1–4 were determined by single crystal X-ray crystallography. The core of 1 contains an equilateral triangle of ruthenium atoms with one capping selenium, one bridging dpph, one doubly bridging carbonyl and seven terminal carbonyl ligands. Complexes 2–4 have a square-pyramidal structure with two metal and two chalcogenide atoms alternating in the basal plane and the third metal atom at the apex of the pyramid, and belong to the family of well-known nido clusters with seven skeletal electron pairs. 相似文献
88.
Branchadell V Crévisy C Grée R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(22):5795-5803
The tandem isomerization-aldolization reaction between allyl alcohol and formaldehyde mediated by [Fe(CO)3] was studied with the density functional B3LYP method. Starting from the key [(enol)Fe(CO)3] complex, several reaction paths for the reaction with formaldehyde were explored. The results show that the most favorable reaction path involves first an enol/allyl alcohol ligand-exchange process followed by direct condensation of formaldehyde with the free enol. During this process, formation of the new C-C bond takes place simultaneously with a proton transfer between the enol and the aldehyde. Therefore, the role of [Fe(CO)3] is to catalyze the allyl alcohol to enol isomerization affording the free enol, which adds to the aldehyde in a carbonyl-ene type reaction. Similar results were obtained for the reaction between allyl alcohol and acetaldehyde. 相似文献
89.
90.
The oxidative cyclization of 5-(2-amino-5-methoxycarbonylphenyl)-substituted tricarbonyl[η4-cyclohexa-1,3-diene]iron complexes by air in protic medium provides the corresponding tricarbonyl[η4-4a,9a-dihydro-9H-carbazole]iron complexes. This procedure is applied to the total synthesis of the 3-methoxycarbonylcarbazole alkaloids mukonine and mukonidine. 相似文献