Fulminate complexes

Recent work (36) has shown that square planar nickel(II) triad fulminates can be prepared. However, these complexes are stabilized by bulky cations, for example, (C6Hs)4As+, that tend to hinder chain formation. 

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The preparation of a non-explosive and thermally stable fulminate complex, Et4N+[Ag(CNO)2], has been described and 14NNMR and IR spectra have been recorded (6 = +164 p.p.m. in CH2C12, cf. NOi 18 2ysCNO = 2294, yasCNO = 2119, ysCNO = 1144 cm-1). 

Most fulminates are very dangerously explosive, but this appears not to be the case for transition metal complexes containing tetraphenylarsonium, tetrapropylammonium or other very large cations. Much recent work on fulminate complexes has involved these compounds, and, as a result of it, the very close analogy with cyano complexes is now established beyond doubt. 

In addition to the phosphineplatinum(II) fulminate complexes mentioned already, many other mixed complexes have been prepared and their vibrational spectra studied.4,35 Equations (2)-(6) illustrate typical preparations. In each case the fulminato complex formed closely resembles the... 

Beck and coworkers211 have reviewed transition metal complexes of the fulminate ion, CNO, which bonds to the metal via the carbon atom. Fulminate complexes are, in general, similar to those with CN ligands. An extensive series of stable, non-explosive fulminates has been examined, including [Ir(CNO)6](AsPh4)3. [Ir(CNO)6]3- was prepared from hydrated iridium(III) chloride and Hg(CNO)2, and characterized by IR spectroscopy.21"1... 

The fulminate (CNO ) ion may coordinate to a metal through the carbon (M—CNO) or the oxygen (M—ONC) or both. So far, all the complexes containing the CNO group are presumed to be C-bonded. Table 111-44 lists the observed CNO frequencies of typical fulminate complexes. Thus far, not much work has been done on fulminato complexes. 

The visible and ultraviolet spectra of various fulminate complexes have been determined in order to estimate the ligand field suength of the fulminate ion CNO". The absorption bands of the diamagnetic (1) octahedral fulminate complexes [FefCNO) ], [Fe(CN) CNO], [Co(CNO) ] have been assigned from the wavenumbers of the two ligand field bands ( -> Tig and... 

B2 RECENT STUDES ON FULMINATE COMPLEXES, W. Beck,... 

The fulminate complex, [Et4N][W(CNO)(CO)5], isomerizes to give an isocyanate complex, [Et4N][W(NCO)(CO)5l, in a variety of solvents.23 The solvent-dependent rate of isomerization was found to increase in the order tetrahydrofuran < acetone < chloroform < dichloromethane. Isomerization did not take place in methanol due to stabilization of the fulminate by hydrogen bonding with the solvent. 

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