Dalton Transactions

doi: 10.1039/b900244hpmid: N/A

doi: 10.1039/b900245fpmid: N/A

doi: 10.1039/b900246bpmid: N/A

Nixon, Tracy D.; Whittlesey, Michael K.; Williams, Jonathan M. J.

doi: 10.1039/b813383bpmid: 19156265

The reactivity of alcohols can be enhanced by the temporary removal of hydrogen using a transition metal catalyst to generate an intermediate aldehyde or ketone. The so-formed carbonyl compound has a greater reactivity towards nucleophilic addition accommodating the in situ formation of imines or alkenes. The return of hydrogen from the catalyst leads to the formation of new C–N and C–C bonds, often with water as the only reaction by-product.

He, Haiyan; Dai, Fangna; Sun, Daofeng

doi: 10.1039/b815935apmid: 19156266

Applying a nonplanar dicarboxylate ligand, a new 3D metal–organic framework, Zn(TBDC1)1/2(TBDC2)1/2 (1), possessing a rare (3,5)-connected net has been synthesized and characterized; complex 1 can be formed from a 2D double layer by thermally liberating the coordinated water and dmf molecules, simultaneous with luminescence-increased changes.

Huang, Yuan-Biao; Jin, Guo-Xin

doi: 10.1039/b820798bpmid: 19156267

Half-sandwich chromium(iii) complexes bearing β-ketoiminato and β-diketiminate ligands were synthesized and employed as catalysts for ethylene polymerization in the presence of triethylaluminium.

Rangheard, Claudine; Proriol, David; Olivier-Bourbigou, Hélène; Braunstein, Pierre

doi: 10.1039/b817726kpmid: 19156268

Reactions of acetylpyridine derivatives with 8-aminoquinolines provide a general and simple access to an unexpected class of versatile N,N,N ligands, which offer interesting perspectives in coordination chemistry.

Schenk, Christian; Drost, Christian; Schnepf, Andreas

doi: 10.1039/b818931epmid: 19156269

The reaction of Ar3GeBr (Ar = 2,6-(OtBu)2C6H3), which is the side product of the synthesis of the metalloid germanium cluster compound Ge8Ar6, with the silver salt of the weakly coordinating anion (WCA) [Al(ORf)4]− (Rf = C(CF3)3) gives the free germyl cation Ar3Ge+. Quantum chemical calculations open an insight into the bonding situation of this first free cation exhibiting aryl ligands and a first reaction leading to Ar3GeOH is presented.

Wang, Rongming; Camacho-Fernandez, Miguel A.; Xu, Wei; Zhang, Jian; Li, Lijuan

doi: 10.1039/b810230apmid: 19156270

A series of Roussin's red salt esters [Fe2(μ-RS)2(NO)4] (R = n-Pr (1), t-Bu (2), 6-methyl-2-pyridyl (3) and 4,6-dimethyl-2-pyrimidyl (4)) were synthesized by the reaction of Fe(NO)2(CO)2 with thiols or thiolates. Complexes 1–4 were characterized by IR, UV-vis, 1H-NMR, electrochemistry, and single-crystal X-ray diffraction analysis. The IR spectra of complexes 1–4 display one weak and two strong NO stretching frequencies (νNO) in solution, but only two strong νNO in the solid. Density functional theoretical (DFT) calculations using complex 1 as model suggest that two spatial isomers of these complexes bear a 3 kcal energy difference in solution. Frequency calculations of the two isomers provide insight on the origin of the vibrational bands and explain the IR observation of complexes 1–4 in the solid state and in solution. Cyclic voltammetry shows two quasi-reversible, one-electron reductions for complexes 1–2 and one quasi-reversible, one-electron reduction for complexes 3–4. The paramagnetic complexes [Fe2(μ-RS)2(NO)4]− (1−–4−), which are prepared by the chemical reduction of neutral complexes [Fe2(μ-RS)2(NO)4] (1–4), have also been investigated by EPR spectroscopy. Interestingly, the EPR spectra of complexes [Fe2(μ-RS)2(NO)4]− (1−–4−) exhibit an isotropic signal of g = 1.998–2.004 without hyperfine splitting in the temperature range 180–298 K. The observations are consistent with the results of the calculations, which reveal that the unpaired electron is dominantly delocalized over the two sulfur and two iron atoms. The difference of the g values between the reduced form of Roussin's red ester and the typical dinitrosyl iron complexes is explained, for the first time, by the difference in unpaired electron distributions between the two types of complexes, which provides the theoretical bases for the use of g values as a spectroscopic tool to differentiate these biologically active complexes.

Schulze, Benjamin; Friebe, Christian; Hager, Martin D.; Winter, Andreas; Hoogenboom, Richard; Görls, Helmar; Schubert, Ulrich S.

doi: 10.1039/b813925cpmid: 19156271

The synthesis of a series of heteroleptic ruthenium(ii)-complexes containing both, 2,2′:6′,2″-terpyridine and 2,6-bis(1H-1,2,3-triazol-4-yl)pyridine, is reported for the first time. The provided complexes feature photophysical and electrochemical properties in between those known for the respective homoleptic complexes. The flexibility with respect to lateral functional groups to be introduced into the complexes underlines the high potential for further functionalization steps.