Complexes containing nitrogen ligands

Dark blue [Tc (phcn)3]Cl was synthesized by controlled potential reduetion of a M solution of Te (phen)3]Cl2 in 0.15 M NaCl under argon at a platinum eath-ode at -1.2 V v.r the saturated Ag/AgCl electrode. The compound was identified by its FAB mass spectrum. The turquoise solution of Tc (phen)3 in CH2CI2 has an absorption maximum at 630 nm and is readily oxidized in air to Tc (phen)3p [603]  

Reaction of NI 14X06)4 with excess hydralazine in dry ethanol gives the cationic tris-diazene complex [Tc (CsH3N2N=NH)3]  

Hydralazine serves concomitantly as the reducing agent. The dark green tetraphen-ylborate salt is air-stable, freely soluble in ethanol, but stable in solution only in the presence of excess ligand. This property prevented recrystallization for X-ray structure analysis. The compound was characterized by FAB-MS, IR. Tc NMR, and cyclic voltammetry [604]. 

A HviJrido-bisn.2-bis(diphcnvlphosphino-ethanc)l-dinitr() cn-lochnetium(I). [IITc(N2)(dppc)2l [606J. 

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The first example of acylpaUadation of dienes appeared in 1993. It involved a stoichiometric reaction of 1,2-dienes (allenes) with acetylpalladium complexes containing nitrogen ligands (Scheme For example, bipyridine (Bipy) or terpyridine (Terpy) cationic acetylpalladium complexes readily react with allenes to form Tr-aUylpaUadium complexes in quantitative yields. Terpy, a tridentate ligand, favors rj -complexes, while Bipy, a biden-tate ligand, favors rj -complexes. 

The most extensively studied europium complexes are the (3-dike-tonates [635—644] although the author has tried to concentrate on complexes containing nitrogen heterocycles [373, 401, 645] as ligands. In both case the complexes fluoresce via the IMET mechanism. 

Complexes containing nitrogen donor ligands such as [(MeCp)2YbNH2]2 have been characterized and the complex is found to be a centro symmetric dimer in which the plane of Yb2N2 part is nearly orthogonal to the plane of the two ring centroids and Yb atoms [116]. 

The majority of nickel(I) complexes contain phosphine ligands, or closely related ones, and have tetrahedral or tbp structures. They are paramagnetic as expected for d9 configurations. The tetrahedral compounds NiX(PPh3)3 (X = Q, Br, and I) were among the first of this sort to be isolated they decompose only slowly in air and are stable for long periods of time under nitrogen. Electrolytic reductions of... 

XVI. Transition Metal Complexes Containing Other Ligands with Nitrogen,... 

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