Carbon, isotopic, hydrocarbons labeled

In effect, the methyl group and the functionalized carbon center are converted to the nitrile functional group. However, as shown by isotope labeling experiments, ammoxidation of a hydrocarbon having an allylic hydrogen produces a symmetric intermediate wherein the nitrile functional group can be incorporated into either end of the allylic intermediate (see below). Thus, ammoxidation reactions can be divided into three major classes. The first is ammoxidation of a methyl group, effectively, to a nitrile functionality. 

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