Azido complexes

Thionitrosyl complexes have already been briefly mentioned on p. 453 and have recently been reviewed.They were first made " by reacting azido complexes directly with... 

The azido complex [(T) -Cp )(N3)Rh( j.-N3),Rh(N3)(Ti -Cp )] with trifluoroace-tonitrile gives the tetrazole complex with two terminal and one bridging tetrazolate ligands as well as one unreacted bridging azido group, 193... 

IC6H4).2348,2349 Amidinato gold(I) complexes have been described and are dinuclear, as [Au2 C(Ph)(NTMS)2 2]475 (398) or tetranuclear as [Au4 CH(NPh)2 4].2350 The triazenido ions RN3R react with Aul in liquid ammonia to form the tetranuclear complex (399), which has an analogous structure to that of the tetranuclear formamidinato compound. 1 The structure of the azido complex [Au(N3)(PPh3)] has been reported.1736... 

The complex azide is highly explosive and must be handled with extreme care. The analogous potassium and caesium derivatives of zinc azide and nickel azide deflagrate strongly in a flame and some are shock-sensitive [1], The potassium salt alone out of 8 azido-complexes exploded during X-irradiation in an ESCA study [2],... 

The coordination of the dinitrogen ligand is maintained when traTO-[Re(N2)Cl(dppe)2] is exposed to NaX salts (X = NCS, NCO , Ns ) in THF/MeOH solutions. The isothiocyanato and azido complexes of type (276) have been studied by X-ray structural analysis.A Re— N2 bond length of 1.951 A is observed for the NCS compound which is somewhat shorter than that in the starting material and indicates a considerable degree of double bond character. 

Azido complexes of Ru include [RuH(N3)(dmpe)2], formed by reacting NaN3 with [RuH2(dmpe)2] (dmpe= l,2-bis(dimethylphosphino)ethane). The reaction of NaN3 with [RUCI2 (depe)2] yields tra 5-[Ru(N3)2(depe)2] (depe= l,2-bis(diethylphosphino)ethane). A related complex is tra 5-[Ru(N3)2(PMe3)4] conversion to the cix-isomer occurs and has been followed by P NMR spectroscopy and cyclic voltammetry. ... 

Treatment of the azido complexes 19 with CO leads also to the migration of the N3 ligand to the aiienyiidene unit (Scheme 2.9). Nevertheless, the initially formed azido-alkynyl compounds 20 are in this case thermally unstable, evolving slowly into the metallated acrylonitrile derivatives 23 via extrusion of N2. The mechanism of formation of 23 involves the migration of the azido moiety from Cy to the C atom of the alkynyl ligand to generate the allenyl intermediates 21, which by elimination of... 

The reactions of butatrienylidene iridium complexes with CO depend strongly on the trans ligand. The trans chloro complex 11 reversibly adds CO to form a five-coordinate butatrienylidene complex 31 whereas the trans azido complex yields with CO an alkenyl(azido)ethynyl complex (32) and the trans methyl complex the alky-nylalkenyl complex 33 (Scheme 3.31) [3]. 

I also hope that someone would comment regarding Dr. Yalman s comments about the reaction between the nitrite ion and the azido complex. One finds that the scavenging activity of—I believe it was bromide and thiocyanate—is much more effective in the presence than in the absence of nitrite in the azide system. The... 

Dr. Wilmarth With respect to the reaction of the azido complex and nitrous acid, since this work was done by Dr. Haim, I think he should comment if he cares to do so. 

In addition, I think workers in Dr. Taube s lab have studied in some detail the reaction of a number of azido complexes with nitrous acid, and it might be interesting to have a few comments on this work. 

Albert Haim Regarding these questions of the reactions of the azido complexes with nitrous acid, there are two systems that I have tried to explore the azidopentammine-cobalt(III) complex and the azidopentacyanocobalt(III) complex. 

Many of these compds are expl and deton when heated or struck (See also Ref 21, p 150-4 and Azido Complexes under Ammines)... 

Photolysis of the azido complex CrN3(salen)-2H20 produces1110 the nitrido chromium(V) complex CrN(salen)-H20 and the reaction1111 of [Cr(salen)(H20)2]+ with iodosylbenzene gives the oxo chromium(V) derivative [CrO(salen)]2+ chromium(III) porphyrin complexes behave similarly (Section 35.4.9.1). 

The most common preparative route for MoVI nitrido complexes involves the reaction of azides such as C1N3 or Me3SiN3 with lower valent Mo complexes.252 The resultant azido complexes are often unstable and eliminate N2 to form the nitrido complex as shown in equations (23) and (24) or equation (25). 

The reversed reaction, i.e. attack of CO on the corresponding transition metal azido complex, sometimes also provides an attractive route for the synthesis of isocyanate complexes, e.g. the reaction of CO with, for example, Co(N3)(DH)2(PPh3),344 Rh(f/5-C5Me5)(N3)4276 or Rh(N3)(cod).344... 

Furthermore, isothiocyanate complexes can be prepared starting from the metal-azido complexes and reacting these with CS2. These reactions most probably proceed via 1,3-dipolar cycloaddition reactions.354 Syntheses of isothiocyanato complexes via this route are known for several metals (see, for example, ref. 355 for a synthesis involving Co). In these reactions formation of a cyclic intermediate (cf. equation 24) could be established. 

As an extension of earlier work (453), the insertions of isocyanides into the metal-nitrogen bond in the azido complexes Co(N3)(cheIate)L (chelate = dianion of jV,iV-o-phenylenebis(salicylidenimine) L = PPh3, py or free coordination site) has been investigated. The tetrazole complexes (109)... 

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