Thermally induced dual P–C bond cleavage routes from the imido-capped cluster Ru3(CO)7(μ3-CO)(μ3-NPh)(bpcd): synthesis, spectroscopic properties, and X-ray diffraction structures of Ru3(CO)7(μ3-CO)(μ3-NPh)(bpcd), Ru3(CO)5(μ2-CO)2(μ3-NPh)(μ2-PPh2)[μ,η1,η1-CC(PPh2)C(O)CH2C(O)], Ru3(CO)6(μ2-CO)(μ3-NPh)(μ-PhCO)[μ2,η2,η1-PPhCC(PPh2)C(O)CH2C(O)], and Ru3(CO)9(μ3-NPh)(μ3-PPh)

2004 ◽  
Vol 689 (21) ◽  
pp. 3426-3437 ◽  
Author(s):  
Simon G. Bott ◽  
Huafeng Shen ◽  
Michael G. Richmond
2008 ◽  
Vol 63 (3) ◽  
pp. 339-341 ◽  
Author(s):  
Ajay Venugopal ◽  
Alexander Willner ◽  
Norbert W. Mitzel

The reaction of N,O-bis(trimethylsilyl)hydroxylamine with potassium hydride in pentane affords a product of the formula {K6[OSiMe3]4[ON(SiMe3)2]2}, resulting from deprotonation followed by N-O bond cleavage and 1,2-silylshift. The compound was characterised by elemental analysis and by single crystal X-ray diffraction. The aggregate consists of a K3O3 bis-cubane core, with N(SiMe3)2 groups at the oxygen atoms shared by the two cubes, andMe3Si groups attached to the four O vertices. Two weak K···N interactions are also detected in the solid state structure.


2013 ◽  
Vol 66 (11) ◽  
pp. 1447 ◽  
Author(s):  
James E. M. Lewis ◽  
James D. Crowley

A series of copper(ii) complexes of the ligand 2,6-bis(pyridin-3-ylethynyl)pyridine have been synthesised and characterised by 1H and DOSY NMR, IR and UV-Vis spectroscopies, mass spectrometry, elemental analysis and single crystal X-ray diffraction. In solution these systems display almost identical spectroscopic properties, however the solid state structures are shown to vary widely, depending upon the choice of anion. The tetrafluoroborate salt was revealed to be a discrete Cu2L4 cage-like helicate. The tosylate salt, whilst of the same Cu2L4 stoichiometry, was shown to be a coordination polymer. Finally the nitrate salt structure was observed to be a discrete Cu2L2 metallocycle.


2003 ◽  
Vol 42 (19) ◽  
pp. 6024-6031 ◽  
Author(s):  
Vladimir B. Arion ◽  
Erwin Reisner ◽  
Madeleine Fremuth ◽  
Michael A. Jakupec ◽  
Bernhard K. Keppler ◽  
...  

2007 ◽  
Vol 62 (3) ◽  
pp. 427-438 ◽  
Author(s):  
Vincenzo G. Albano ◽  
Luigi Busetto ◽  
Fabio Marchetti ◽  
Magda Monari ◽  
Stefano Zacchini ◽  
...  

The diiron aminocarbyne complexes [Fe2{μ-CN(Me)(R)}(μ-CO)(CO)(NCMe)(Cp)2][SO3CF3] (R = Xy1, 1a; R = Me, 1b; R = CH2Ph, 1c; Xy1 = 2,6-Me2C6H3) undergo replacement of the coordinated nitrile by halides, diethyldithiocarbamate, and dicyanomethanide to give [Fe2{μ-CN(Me) (R)}(μ-CO)(CO)(X)(Cp)2] complexes (R = Me, X = Br, 4a; R = Me, X = I, 4b; R = CH2Ph, X = Cl, 4c; R = CH2Ph, X = Br, 4d; R = CH2Ph, X = I, 4e; R = Xy1, X = SC(S)NEt2, 5a; R = Me, X = SC(S)NEt2, 5b; R = Xy1, X = CH(CN)2, 7), in good yields. The molecular structure of 5a shows an unusual η1 coordination mode of the dithiocarbamate ligand. Similarly, treatment of [M2{μ-CN(Me) (R)}(μ-CO)(CO)(NCMe)(Cp)2][SO3CF3] (M = Fe, R = Xy1, 1a; M = Fe, R = Me, 1b; M = Ru, R = Xy1, 2a; M = Ru, R = Me, 2b) with a series of phosphanes generates the cationic complexes [M2{μ- CN(Me)(R)}(μ-CO)(CO)(P)(Cp)2][SO3CF3] (M = Fe, R = Xy1, P = PPh2H, 6a; M = Fe, R = Xy1, P = PPh3, 6b; M = Fe, R = Xy1, P = PMe3, 6c; M = Fe, R = Me, P = PMe2Ph, 6d; M = Fe, R = Me, P = PPh3, 6e; M = Fe, R = Me, P = PMePh2, 6f; M = Ru, R = Xy1, P = PPh2H, 6g; M = Ru, R = Me, P = PPh2H, 6h), in high yields. The molecular structure of 6a has been elucidated by an X-ray diffraction study. The reactions of [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO)(NCR′)(Cp)2][SO3CF3] [R′ = Me, 1a; R′ = tBu, 3] with PhLi and PPh2Li yield [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO)(Ph)(Cp)2] (8) and [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO)(PPh2)(Cp)2] (9), respectively. The molecular structure of 8 has been ascertained by X-ray diffraction. Conversely, the reaction of 1a with MeLi generates the aminoalkylidene compound [Fe2{C(Me)N(Me)(Xy1)}(μ-CO)2(CO)(Cp)2] (10).Finally, the acetone complex [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO)(OCMe2)(Cp)2][SO3CF3] (12) reacts with lithium acetylides to give complexes [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO)(C≡CR)(Cp)2] (R = p-C6H4Me, 11a; R = Ph, 11b; R = SiMe3, 11c), in high yields. Filtration through alumina of a solution of 11a in CH2Cl2 results in hydration of the acetylide group and C-Si bond cleavage, affording [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO){C(O)Me}(Cp)2] (12).


Clay Minerals ◽  
2007 ◽  
Vol 42 (2) ◽  
pp. 213-231 ◽  
Author(s):  
C. Henry ◽  
J.-Y. Boisson ◽  
A. Bouchet ◽  
A. Meunier

AbstractA mixed-layer illite-smectite, illite-rich calcareous mudstone intruded by a basaltic dyke at the Perthus Pass (southern Massif Central, France) allows us to study the transformation of clays subjected to a brief thermal gradient. X-ray diffraction, scanning electron microscopy, electron microprobe and atomic absorption spectroscopy analyses were performed on samples at variable distances from the mudstone-dyke contacts.A roughly similar evolution is seen on both sides of the dyke: quartz, calcite, kaolinite and illite disappear; Ca-silicates, albite and saponite-beidellite form, late meteoric halloysite crystallizes in open fractures.Chemical and mineralogical transformations are related to heat diffusion from the dyke. Theoretical calculations highlight the influence of the dyke orientation. The mineralogical reactions observed in rocks are similar to those observed in experimental conditions. The formation of new swelling phases with a high retention capacity linked to a short duration, large-temperature increase, should constitute a positive process for Repository Performance Assessment.


2008 ◽  
Vol 23 (2) ◽  
pp. 565-569 ◽  
Author(s):  
Runrun Duan ◽  
Michael S. Haluska ◽  
Robert F. Speyer

Compositions of xBiLaO3–(1 − x) PbTiO3 over the range 0 ≤ x ≤ 0.225 were calcined and sintered. The dielectric constant with temperature and differential scanning calorimetry measurements were in excellent agreement with respect to Curie-like tetragonal to cubic transformations starting at 495 °C for pure PbTiO3, shifting to lower temperatures with increasing x. For compositions of x ≥ 0.05, a second higher-temperature (∼600 °C) endotherm, and matching dielectric anomaly, were consistently observed, for which there were no structural changes indicated by hot-stage x-ray diffraction. This transformation was speculated to be based on a thermally induced desegregation of B-site cations.


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