Dalton Transactions

doi: 10.1039/b822632fpmid: N/A

doi: 10.1039/b822636apmid: N/A

Hnyk, Drahomír; Rankin, David W. H.

doi: 10.1039/b806774kpmid: 19378550

The development of modern computational methods, linked to improved methods for analysis of experimental gas-phase structural data, has allowed the stereochemistry of many boranes and heteroboranes to be determined with great accuracy over the past two decades. Many of these compounds have been prepared in the Institute of Inorganic Chemistry of the Academy of Sciences of the Czech Republic, and gas-phase electron diffraction (GED) data have been obtained mainly at the University of Edinburgh. Structural tools based on the concerted use of GED and computations of the geometries and 11B chemical shifts (MOCED, SARACEN) have also been employed. The results of this extended programme of research are reviewed here. Many different closo-, nido-, arachno-, and hypho- geometrical shapes, as well as some that do not obey Wade's rules, are included. The outlook for the future of this type of structural chemistry research is assessed.

Meilikhov, Mikhail; Yusenko, Kirill; Fischer, Roland A.

doi: 10.1039/b820882bpmid: 19378551

Ferrocene is strongly adsorbed by the highly porous metal-organic framework compound [Al(OH)(bdc)]x (MIL-53; bdc = 1,4-benzenedicarboxylate). The structure of the crystalline phase {[Fe(η5-C5H5)2][Al(OH)(bdc)]2}x was determined by X-ray powder diffraction and Rietveld methods. The ferrocene molecules are arranged in a 1D chain-like fashion and their cyclopentadienyl rings are oriented almost parallel to the O3Al faces of the {AlO6} octahedra without π-stacking to the bdc.

Maria, Leonor; Fernandes, Célia; Garcia, Raquel; Gano, Lurdes; Paulo, António; Santos, Isabel Cordeiro; Santos, Isabel

doi: 10.1039/b817451bpmid: 19378552

Novel ether-containing tris(pyrazolyl)methane chelators stabilize the -[Tc(CO)] moiety providing complexes with significant, fast and stable heart uptake, together with a extremely fast liver clearance.

Knight, Edward R.; Cowley, Andrew R.; Hogarth, Graeme; Wilton-Ely, James D. E. T.

doi: 10.1039/b814476apmid: 19378553

A dithiocarbamate-based methodology is employed to prepare linked heteromultimetallic complexes and then further exploited in the surface functionalisation of gold nanoparticles.

Khairul, Wan M.; Fox, Mark A.; Zaitseva, Natasha N.; Gaudio, Maryka; Yufit, Dmitry S.; Skelton, Brian W.; White, Allan H.; Howard, Judith A. K.; Bruce, Michael I.; Low, Paul J.

doi: 10.1039/b809960jpmid: 19378554

Marson, Angelica; Ernsting, Johanneke E.; Lutz, Martin; Spek, Anthony L.; van Leeuwen, Piet W. N. M.; Kamer, Paul C. J.

doi: 10.1039/b814469apmid: 19378555

The synthesis of the calix[4]arene-based P,N-ligand 3 (5,11,17,23-tetra-tert-butyl-25-[(2-quinolylmethyl)oxy]-26,27,28-(μ3-phosphorustrioxy)calix[4]arene), in which the nitrogen atom-containing moiety has been introduced at the lower rim of the cavity prior to P-functionalisation, is described and its coordination properties investigated. In the crystal structure, the calix[4]-cavity adopts a cone conformation with an exo orientation of the phosphorus lone pair enabling P-N chelation. 1H, 13C, 31P and 1H{15N} HMQC NMR spectra indicated that, in complexes [PdCl(CH3)(3)] (4) and [Rh(CO)Cl(3)] (5), ligand 3 coordinates in a chelating fashion, while in cis-[PtCl2(3)2] (6) and [Rh(acac)(CO)(3)] (7) it behaves as a monodentate ligand, coordinating via the phosphorus atom only. X-Ray crystal structure determinations were performed for [PdCl(CH3)(3)] (4) and cis-[PtCl2(3)2] (6). The cationic Pd complex [Pd(CH3)(CH3CN)(3)][PF6] (8) was found to be active in a CO/ethylene copolymerisation reaction. Good selectivities were observed for the Pd-catalysed allylic alkylation of cinnamyl acetate with in situ prepared catalysts. [Rh(acac)(CO)2] modified with ligand 3 catalyses the hydroformylation of 1-octene with low selectivities towards linear aldehydes. High-pressure NMR experiments on the hydrido carbonyl rhodium(3) were inconclusive, different species were formed.

Dabb, Serin L.; Ho, Joanne H. H.; Hodgson, Richard; Messerle, Barbara A.; Wagler, Jörg

doi: 10.1039/b814168apmid: 19378556

A series of cationic rhodium(i) and iridium(i) complexes of the type [M(L∩L)(C2)]BArF24 (where M = Rh or Ir, L∩L = bis(pyrazol-1-yl)methane (bpm), bis(N-methylimidazol-2-yl)methane (bim) or 1-(2-(diphenylphosphino)ethyl)-3,5-diphenylpyrazole (Ph2PyP), C2 = 1,5-cyclooctadiene (COD) or (CO)2 and BArF24 = tetrakis[3,5-bis(trifluoromethyl)phenyl]borate) were synthesised in good yields. The solid-state structure of a number of complexes, including [Ir(Ph2PyP)(COD)]BArF24, [Ir(bpm)(COD)]BArF24 and [Ir(bim)(COD)]BArF24 was determined using X-ray crystallography. The efficiency of the complexes as catalysts for the intramolecular hydroamination of 4-phenyl-3-butyn-1-amine, 4-pentyn-1-amine and 2-(2-phenylethynyl)aniline was established. The incorporation of the BArF24− counter-ion in the Rh(i) and Ir(i) complexes was found to significantly improve the catalytic activity of the complexes, compared to the analogous Rh(i) and Ir(i) complexes containing BPh4− as the counter-ion. Excellent conversions were achieved for the cyclisation of 2-(2-phenylethynyl)aniline to 2-phenylindole using [Rh(bpm)(CO)2]BArF24 as a catalyst. The use of a microwave reactor for enhancing the catalysed reactions was also investigated.

Klapötke, Thomas M.; Stierstorfer, Jörg

doi: 10.1039/b811767epmid: 19378557

The highly energetic isomers azidoformamidinium dinitramide (1) and 5-aminotetrazolium dinitramide (2) were synthesized by the reaction of potassium dinitramide and azidoformamidinium perchlorate and 5-aminotetrazolium perchlorate, respectively. Both compounds are characterized by an oxygen balance of Ω = 0. In addition, 1H-tetrazolium dinitramide (3) and 2-methyl-5-aminotetrazolium dinitramide (4) were synthesized using 1H-tetrazolium perchlorate (5) and 2-methyl-5-aminotetrazolium perchlorate. A full characterization of the chemical properties (single-crystal X-ray diffraction, IR and Raman spectroscopy, multinuclear NMR spectroscopy, differential scanning calorimetry and mass spectrometry) as well as of the energetic characteristics is given in this work. The heats of formation were calculated (CBS-4M) in an extensive computational study. The detonation parameters of compounds 1–4 were computed using the EXPLO5 software resulting in auspicious values for potential applications as high explosives. For 2 this was confirmed by a “Koenen” steel sleeve test using a critical diameter of 10 mm. In addition, the sensitivities were tested using the BAM drop hammer, BAM friction tester and an electrical spark device. Finally, the synthesis and characterization, including the X-ray structure of the highly hygroscopic 1H-tetrazolium perchlorate (5), is given in this work.