Methyleneamido complexes

Several synthetic methods for the synthesis of methyleneamido complexes have been developed. The only method which shows any degree of generality is the use of metalloketimines. The other synthetic methods listed below have not been studied in depth. 

In certain early transition metal complexes and in metal clusters, organic nitriles can insert into metal-hydrogen or metal-carbon bonds (equations 92 and 93). Similarly, nucleophilic attack at coordinated nitrile can yield methyleneamido complexes (equation 94). 

The protolysis of a basic metal-alkyl by the acidic proton in ketimines can lead to methyleneamido complexes (equation 95). 

A two metal, two-electron (not two metal, four-electron) reductive coupling of organic nitriles can lead to dimeric methyleneamido complexes (equation 97). 

Carefully controlled oxidation of ligated primary amines has been used to prepare methyleneamido complexes (equation 98). 

Azines and 2-bromo-2-nitrosoalkanes have been used to produce methyleneamido complexes from low valent carbonyl complexes yields were mediocre and by-products were generated (equations 100 and 101). Other attempts to use azines or iV-bromoketimines have failed to give useful products.216... 

X-Ray photon emission spectra of some Mo and W methyleneamido complexes have been measured. The limited data show that the bind energies of N(15) are insensitive to changes in structure and bonding environment. The binding energies for the metals show some variation (1.0-1.5eV) which has been correlated with v(CO) of carbonyl coligands.220... 

Table 10 gives a listing of methyleneamido complexes. The listing includes several bis(methylene-amido) complexes and representatives from most of the metals in the transition series with the exception of complexes from the copper group. 

Methanol, JV-methyIumdazol-2-yldi pyrid-2-yl)-, 88 metal complexes, 89 Methionine metal complexes, 749 Methyleneamido complexes transition metal, 125,129 bonding, 127 reactions, 128 spectroscopy, 128 structures, 127,128 synthesis, 126... 

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