Other Nitrogen Donors

Other Nitrogen Donors. The trigonal-bipyramidal [Ru(CO)2(NNPh)(PPh3)2]PF6 has been prepared from Ru(CO)3(PPh3)2 and PhN two isomers co-exist in solution. Addition of halide ions give rise to an octahedral complex with a doubly bent RuN2Ph moiety.  

The osmotic coefficient of [Ru(phen)3]S04 has been measured at 298 K and the closest approach distance of the ions calculated to be 11.5 A.  

L] undergo a reversible two-electron reduction to Ru diamine complexes. The 

Rieder, U. Hauser, H. Siegenthaler, E. Schmidt, and A. Ludi, Inorg. Chem., 1975,14, 1902. 

Substitution reactions of cis-Ru(bipy)2X2 (X = F, Cl, or Br) with methyl-substituted pyridines have been studied in various non-aqueous solvents and the results indicate a dissociative mechanism via [Ru(bipy)2X] as the intermediate. The outer-sphere electron transfer between [Ru(NH3)g] and [(NH3)5Co02Co(NH3)s] has been monitored. Flash photolysis at the intense metal-to-ligand CT band (508 nm) of the pyrazine complex [(NH3)5Ru (pyr)Cu ] causes an intramolecular electron transfer to [(NH3)5Ru (pyr)Cu ]. This allowed the unimolecular reverse electron-transfer process to be monitored. 

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Other nitrogen donor ligands. A series of complexes of the unusual 1,3-di-p-tolyltriazenido ligand (L) (9) has been prepared, including [OsH(CO)-(PPh3)2L]. The i.r. spectrum of the diamagnetic, air-stable complex indicates bidentate co-ordination of... 

The dissociation rate constant was found to be almost independent of solvent composition and the rapid decrease in the stability constant near jtMecN = 0 was therefore due to the variation in the formation rate constant. The constant value of kd, suggested that in the transition state the Ag1 ion was bound to the [2.2.2] nitrogen atoms in a manner similar to that usually found with other nitrogen donors, for example, acetonitrile.481... 

In common with other nitrogen donor ligands, the majority of reported coordination compounds are with later d transition elements, or early B subgroup elements, in oxidation states of II or III. Tetraaza macrocycles predominate, with 14 followed by 16 as the most common ring sizes. 

Nitrile derivatives of the metal carbonyls have been discussed together with other nitrogen donor molecules in a number of contexts. Much of the early work has been reviewed by Manuel 337) in his article on Lewis base-metal carbonyl complexes in Volume 3 of this series, and by Stroh-meier 436) in his review of photochemical substitution reactions. In general, nitriles are weaker Lewis donors than phosphorus and nitrogen bases 436), but compared to carbon monoxide, better electron donors but poorer acceptors 427). Force constants and assignments for a series of complexes [(MeCN)jjM(CO)g J (M = Cr, Mo, W) were studied 165, 228, 296) and... 

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