The reaction of (μ-Cl)2Ni2(NHC)2 (NHC = 1,3-bis(2,6-diisopropylphenyl)-1,3-dihydro-2H-imidazol-2-ylidene (IPr) or 1,3-bis(2,6-diisopropylphenyl)imidazolidin-2-ylidene (SIPr)) with either one equivalent of sodium cyclopentadienyl (NaCp) or lithium indenyl (LiInd) results in the formation of diamagnetic NHC supported Ni(I) dimers of the form (μ-Cp)(μ-Cl)Ni2(NHC)2 (NHC = IPr (1 a) or SIPr (1 b); C...

Substituted benzyl alkynyl ethers, prepared from the corresponding α-alkoxy ketones in a two-step sequence involving enol triflate formation and KOtBu-induced E2 elimination, undergo [3,3]-sigmatropic rearrangement/intramolecular 5-exo-dig cyclization at 60 °C to form substituted 2-indanones in good overall yields. 1,3-cis-Disubstituted-2-indanones are formed preferentially when the benzylic su...

[equation--see text] The N-arylation of indoles, including a variety of substituted ones, has been carried out using bulky, electron-rich phosphines as the supporting ligand in combination with Pd(2)(dba)(3). Using this catalyst system, the efficient coupling of indole and a variety of substituted indoles with aryl iodides, bromides, chlorides, and triflates can be achieved.

Reductions of bulky alkynyl-substituted dihalosilanes, BbtSiX(2)(C[triple bond]CR) (Bbt = 2,6-bis[bis(trimethylsilyl)methyl]-4-[tris(trimethylsilyl)methyl]phenyl, R = SiMe(3) or Ph groups, X = halogen), with 2.0 equiv. of lithium naphthalenide gave the first stable 1,2-dialkynyl-substituted disilenes, which constituted extended pi-conjugated systems between Si=Si bond and ethynylene units.

Gold and nickel bisdithiolene complexes with methyl and tert-butyl substituted thiophenetetrathiafulavalenedithiolate ligands (α-mtdt and α-tbtdt) were prepared and characterized. These complexes were obtained, under anaerobic conditions, as tetrabutylammonium salts. The diamagnetic gold monoanion (n-Bu₄N)[Au(α-mtdt)₂] (3) and nickel dianionic species (n-Bu₄N)x[Ni(α-mtdt)₂] (x = 1,2) (4) were s...

We have applied the method to determine the free energy barrier of the chain termination in a Ni-diimine based ethylene polymerization catalyst, 1. In this simulation the Ni diimine core was treated at the Becke88Perdew86 DFT level while the large ortho substituted aryl rings were treated with a molecular mechanics force field (The atoms with the asterisk in structure 1 are the capping atoms). ...

In the title compounds, [Zr2Br6(C11H12N)2], (I) and [ZrBr2(C11H12N)2], (II), the positions of the η5-binding 2-di-methyl-amino-indenyl units are fixed by intra-molecular C-H⋯Br inter-actions involving aromatic or di-methyl-amino H atoms. The binuclear mol-ecule of (I) is located on a general position, while the mononuclear mol-ecule of (II) is situated on a twofold rotation axis. Both ZrIV atom...

Two differently substituted pyrazole ligands have been investigated with regard to the topology of their Pt complexes: upon deprotonation, two mononuclear 1:2 PtII-pyrazole complexes—one sterically unhindered 4-Me-pzH and one bulky 3,5-tBu-pzH (pzH = pyrazole)—yield corresponding PtII-pyrazolato species; former a triangular, trinuclear metallacycle (1), latter dinuclear, half-lantern species (2...