Dalton Transactions Blog

Braunstein and co-workers have formed a dinuclear Ir(I) complex with a bis-NHC ligand in situ from
1,1′-((4,6-dimethyl-1,3-phenylene)bis(methylene))bis(3-methyl-1H-imidazol-3-ium) in
the presence of Cs₂CO₃ and [Ir(µ-Cl)(cod)]₂. Its solid-state structure, determined by X-ray
diffraction, shows a figure-of-eight loop with both the P and M enantiomers being present. Solution NMR studies were also performed to examine the enantiodiscrimination between them.

Read more for FREE until the 29th November 2011 at:

Chiral anion-based NMR enantiodiscrimination of a dinuclear, cationic Ir(I) NHC complex with a figure-of-eight loop structure
Xianghao Liu, Jérôme Lacour and Pierre Braunstein
Dalton Trans., 2012, Advance Article
DOI: 10.1039/C1DT11604E

Also read about the formation of unprecedented eight-membered chelates at:

Contrasting bonding modes of a tridentate bis(oxazoline)phosphine ligand in cobalt and iron vs. palladium complexes: unprecedented N,N-coordination for a N,P,N ligand
Anthony Kermagoret and Pierre Braunstein
Dalton Trans., 2008, 585-587
DOI: 10.1039/B717021C

Oelkers and Sundermeyer, in this HOT Article, present a general approach towards 1,4-diazabutadiene (DAD^S) ligands with various onium cations via acid–base reactions and towards their noble-metal complexes. The solubility and immobilization of such complexes in ILs is quantitatively shown via photometric measurements using a chromophoric Mo(0) DAD^S complex in a toluene/[BMIM]OTf biphasic mixture as a model system. It was shown that complexes with ionic liquid (IL) – typical onium salts of sulfonated diazadienes as ligands are strongly retained in an IL phase in contact with a toluene phase, which may make these ligands potentially useful in IL/organic biphasic catalysis.

Read more for FREE until mid-November:

Sulfonate-tagged 1,4-diazabutadiene (DAD^S) ligands and their noble-metal complexes – synthesis, characterization and immobilization in ionic liquids
Benjamin Oelkers and Jörg Sundermeyer
Dalton Trans., 2011, Advance Article
DOI: 10.1039/C1DT10939A

In this HOT Article, US researchers have presented an in depth reactivity study of alkynylgold species and phosphonates. As protodeauration is the main terminating step in gold catalysis, the effect of labile P–H bonds will be of interest to those studying gold catalysis, as well as those studying phosphite chemistry.

Read more about these gold complexes for FREE until mid-November at:

P–H activation using alkynylgold substrates: steric and electronic effects

Gerald F. Manbeck, Mark C. Kohler, Meghan R. Porter and Robert A. Stockland Jr.
Dalton Trans., 2011, Advance Article
DOI: 10.1039/C1DT11337B

Mike George, Paul Raithby and co-workers using photocrystallography to identify isomers in a nickel complex. Photocrystallography allows the groups to study metastable linkage isomers and they have shown that the technique provides scope for the identification of new species.

Photocrystallography involves the photo-activation of species within a crystalline lattice. It brings a dynamic aspect to X-ray crystallographic experiments, so that reactions within a crystal can be monitored as they occur or the structures of molecules in metastable or short-lived photo-activated states can be determined. Read more about the group’s findings in their Dalton Transactions Hot Article:

Photocrystallographic identification of metastable nitrito linkage isomers in a series of nickel(II) complexes
Simon K. Brayshaw, Timothy L. Easun, Michael W. George, Alexandra M. E. Griffin, Andrew L. Johnson, Paul R. Raithby, Teresa L. Savarese, Stefanie Schiffers, John E. Warren, Mark R. Warren and Simon J. Teat
Dalton Trans., 2011, DOI: 10.1039/C1DT11379H

Phalguni Chaudhuri and colleagues, from the Max-Planck-Institut in Mulheim, Germany, investigate the interactions between a potentially tetradentate tripodal ligand and the biologically important metal, Vanadium. What were the resulting complexes? Find out in  their Hot Article – FREE to read until mid November.

Non-oxo 5-coordinate and 6-coordinate vanadium(IV) complexes with their precursor [LVIII(CH3OH)]0, where L = a trianionic aminetris(phenolate)-[N,O,O,O] donor ligand: a magnetostructural and EPR study
Takashi Kajiwara, Rita Wagner, Eckhard Bill, Thomas Weyhermüller and Phalguni Chaudhuri
Dalton Trans., 2011, DOI: 10.1039/C1DT11277E

In their Dalton Trans. Hot Article, a group of Japanese chemists led by Hisako Sato, used vibrational circular dichroism (VCD) spectroscopy to study the stereochemical properties of a star-burst type tetranuclear Ru(III) complex. By comparing the VCD spectra of eight diastereomeric enantiomers, they were able to see the homo- or hetero-chiral nature of the bridging part of the compound which connected the central core and the peripheral region

Chirality effects on core-periphery connection in a star-burst type tetranuclear Ru(III) complex: application of vibrational circular dichroism spectroscopy
Hisako Sato, Fumi Sato, Masahiro Taniguchi and Akihiko Yamagishi
Dalton Trans., 2012, Advance Article
DOI: 10.1039/C1DT11510C