A series of air-stable nickel complexes of the form L2Ni(aryl) X (L = monodentate phosphine, X = Cl, Br) and LNi(aryl)X (L = bis-phosphine) have been synthesized and are presented as a library of precatalysts suitable for a wide variety of nickel-catalyzed transformations. These complexes are easily synthesized from low-cost NiCl2·6H2O or NiBr2·3H2O and the desired ligand followed by addition o...

Three new coordination polymers have been prepared by hydrothermal reaction of squaric acid, pyrazine and the metal halides FeCl2· 4 H2O, CoBr2 and NiBr2. In their crystal structures the metal atoms are coordinated by four water molecules and two pyrazine ligands within slightly distorted octahedra. The pyrazine ligands connect the metal atoms via μ-N,N’-coordination to linear chains which are ...

We present a comparison of experimental and simulated frequency- and field-domain electron paramagnetic resonance (EPR) spectra of integer and half-integer high-spin transition-metal ion complexes. For the simulation of EPR spectra a new tool within the EPR simulation software EasySpin is introduced, which allows for field- and frequency-domain EPR simulations with the same theoretical model an...

Four examples of para-nitro substituted 2-(arylimino)pyridine-nickel(II) bromide complexes general formula, [2-{(2,6-R-4-NO2C6H2)N=CMe}C5H4N]NiBr2, but differentiable by the steric/electronic properties displayed ortho-groups [R = i-Pr (Ni1), Et (Ni2), CHPh2 (Ni3), CH(4-FPh)2 (Ni4)], have been prepared in good yield. For comparative purposes, meta-nitro complex, [2-{(2,6-i-Pr2-3-NO2-4-(4-FPh)2C...

Phosphinito-imines, a new class of P,N donors, are readily generated by reaction of bulky arylamide anions [RCONAr] (R = Me or t-Bu; Ar = 2,6-i-Pr2C6H4) with chlorophosphines ClP(R)2. In solution, free phosphinito-imines exist in equilibrium with the corresponding amidophosphine tautomers, containing a nitrogen-bound P(R)2 group. However, reacting the tautomer mixtures with metal precursor comp...

The synthesis and reactivity of nickel complexes with the [2-(dimethylamino)ethyl]cyclopentadienyl ligand (CpN) are described. The reaction of NiBr2 with CpNLi leads to the new paramagnetic nickelocene derivative (Cp)2Ni (1), which has been characterized by 1H and 13C NMR, elemental analysis, and mass spectroscopy. Synproportionation of this complex with Ni(CO)4 affords quantitatively the dimer...

By exposing to NaClO aqueous solution (commercial bleach), NiBr2 is transformed quantitatively into an insoluble nickel oxide hydroxide species. This compound contains large surface area and is a beneficial heterogeneous catalyst for oxidizing numerous organic materials. The oxidation of aldehydes and primary alcohols to carboxylic acids and secondary alcohols to ketones is showed wi...

A collection of five related 2-(arylimino)pyridines, 2-{(2,6-(CH(C6H4-p-F)2)2-4- RC6H2)N=CMe}C5H4N, each ortho-substituted with 4,4′-difluorobenzhydryl groups but distinct in the electronic properties para-R substituent (R = Me L1, Et L2, i-Pr L3, F L4, OCF3 L5), were prepared and combined (DME)NiBr2 to form their corresponding LNiBr2 complexes, Ni1–Ni5, high yields. All complexes characterized...