Azide ligand

The influence of boron-bonded ligands on the kinetics and mechanistic pathways of hydrolysis of amine boranes has been examined (37,38). The stoichiometry of trimetbyl amine azidoborane [61652-29-7] hydrolysis in acidic solution is given in equation 10. It is suggested that protonation occurs at the azide ligand enabling its departure as the relatively labile HN species. 

High-valent iron also occurs in -nitrido bridged dimers with linear [Fe °-N=Fe" ]" and [Fe =N=Fe ] " cores [209, 210] (and references therein). Such compounds have been prepared first by thermolysis [247] or photolysis [248] of iron(III)-porphyrin complexes with an azide ligand, (N3). Mixed-valent iron-nitrido porphyrin dimers exhibit valence delocalization as can be inferred from the... 

Coordinated azide ion will undergo a number of reactions which involve attack at the azide ligand. A number of examples are summarized in Scheme 9.1172-1175 The azide ligand is photochemically dissociated from bis azide complexes. Irradiation of Pt(CN)4(N3) gives Pt(CN)4 and the azide radical (equation 366),1176 whereas with Pt(N3)2(PPh3)2 the nitrogen-containing product is believed to be N6 (equation 367).1177... 

Reactions between 5-cyanotetrazole and transition metals, when performed in boiling acetone, lead to hydrolysis of the cyano group and formation of 5-carbamyl tetrazolate complexes (68). Complexes containing 1- or 5-substituted tetrazolate anions can also be obtained by 1,3-dipolar cycloaddition of organic isonitriles (RNC) (15) or nitriles (RCN) (61), respectively, to coordinated azide ligands [Eqs. (3) and (4)]. 

So far only terminal N-bonding of the azide ligand has been reported for Co azide com-plexes.218,273,280 In the case of the Rh azide compounds both terminal274,275 (see 97) and 1,1-/ bonding276 have been found. 

A large amount of structural information is available for the pseudohalide complexes of Cu. Terminal,303-304 317 l,3- i304,318,319 and l,l- i3l8,319b 320 bound azide ligands have been found. For example,... 

One of the earliest Schiff base macrocycles to exhibit a haemocyanine-like structure was the copper(II) perchlorate complex of 5.5 which binds readily to azide or hydroxide.8 The azide complex exhibits two square pyramidal copper binding domains with the basal plane occupied by one pyridyl nitrogen atom and two imine functionalities as well as a terminal azide ligand. The apices of the two pyramidal coordination polyhedra are linked by a single bridging azide anion. Continuing the biomimetic theme, manganese (II) cascade complexes of the unsymmetrical 5.6 have... 

Ligand exchange reactions with nitrido molybdenum complex 56 has been documented (Eq. (19)). Treatment of 56 with 2 equiv. of HX (X = Cl or Br) leads to the formation of 57 which, following treatment with triethylamine, afforded 58, wherein a halide has been substituted for the azide ligand found in 56 [27]. The introduction of a nitride onto a Mov complex has been carried out by treatment of Mom or Mo ... 

Infrared spectroscopy and 13CO experiments show that in this reaction a five-coordinate nickel carbonyl complex with a v(CO) band at 2127 cm 1 forms as an intermediate. In this intermediate, the azide ligand, which had been inert in the [Ni(N3)(S3)] starting complex, evidently is labilized so much that it spontaneously dissociates N2 to form the NCO ligand of the final [Ni(NCO)-(83)] complex. Scheme 28 illustrates the suggested reaction mechanism. 

The azido hgand is particularly versatile as a leaving group, as the displacement is acid catalyzed. Coordinated azide ligands also have the potential to react via 1,3-dipolar cycloaddition with organic isonitriles or nitriles to give 1- or... 

There are many structural studies of copper coordination compounds with azide ligands, mainly of mononuclear and binuclear copper complexes but a few also of trinuclear copper complexes. A comprehensive... 

It is now well known that end-on bridging azide ligands mediate the ferromagnetic exchange between paramagnetic centers [177]. Magnetostructural... 

---