Cyanate ligand

The complex [Co(NH3)5(OS02CF3)]2+ undergoes triflate substitution by cyanate and condensation with acetone to form the unusual bis-bidentate imine complex (213)917 in a reaction reminiscent of the classic Curtis condensation of acetone with ethylenediamine. Apart from the novelty of the synthesis, the reported crystal structure was only the second of a CoN6 complex bearing a cyanate ligand. 

An N-bonded attachment of the cyanate ligands in ZrCl3(NCO) and [M(NCO)6]2" has been established by vibrational spectra, which exhibit a shift of the v(C—O) mode to higher... 

P NMR spectroscopy.53 Steric factors account for the different coordination modes, while the influence of electronic factors is evidenced by the difference in structure between analogous palladium(II) and platinum(II) compounds, for example, the thiocyanates are N- and S-bonded in [Pd(NCS)(SCN)(diars)], but only S-bonded in [Pt(SCN)2(diars)].54 These and other diphosphine or diarsine complexes of palladium(II) with thio- or seleno-cyanate ligands are further discussed in Section 51.8.2.6. 

Only one structure for a transition metal cyanate complex has been reported. In trigonal-bipyramidal Co(terpy)(NCO)2 (98)277 the cyanate ligand is terminal N-bonded. Based on the M—N—C bond angle (160.9°) an M—N(CO) bond distance of about 1.16 A is expected whereas a much shorter bond is found. 

In the Cu-ncyanate complexes the cyanate ligand can be bonded in the terminal N mode321 as well as in the 1,1-ft bridging form.227 The structure of Ag(NCO)305 consists of an infinite —N—Ag— N—Ag— chain as a result of 1,1-ft N-bonding. In contrast [NBudJAgfNCC) ]306 has a discrete molecular structure containing discrete OCN—Ag—NCO units. 

NCO angle remains relatively linear. The mean C=N bond length for the bridging cyanate ligand MC8 is slightly longer than for the terminally bonded cyanate ligand MC7. 

Nucleophilic attack of an azide ion at the carbonyl ligand, followed by elimination of N2, afforded a metal coordinated cyanate ligand (Scheme 8.15) [23]. The kinetic study of the reaction between [r/ -C5H5Fe(CO)2L]+ and NaN3 in... 

Similarly, the cyanate ligand in the cluster Ru4(CO)i3(NCO) may be decar-benylated upen heating te yield nitride clusters which can be enlarged by a sequence ef redex cendensatien reactiens. 

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