Catalytic reactions involving deoxygenation

Thus in this case the catalytic reaction involves the anionic -form o f the nitroalkaneI which in general undergoes reactions at the metal centre di-f-ferent than those observed with the nitro derivatives in their neutral -form (3.2.) However it is interesting to point out the similarity between the probable intermediate formed during the deoxygenation reactions o-f nitro compounds by carbon monoxide <3.2.1.), and the intermediate which should lead to the oxime in the copper-catalysed reactions ... 

The conversion never reaches 100% whatever the reaction time, suggesting deactivation of the catalyst. Indeed, after addition of the epoxide, the intensity of signal B decreases with time. Similarly, the initial red-orange colour fades with time and vanishes at the end of substrate conversion. This colour may be attributed to the active complex. The catalytic site proposed above involves an oxophilic Ni centre. Deactivation might arise from oxidation of this active complex and simultaneous epoxide deoxygenation yielding the small amount of allylic tertiary alcohol la observed (Table 3). 

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