91Ó°ÊÓ

(a. The mechanism of McLafferty rearrangement of pentanal can be shown by the transfer of hydrogen from the gamma position $\text{(}\mathrm{γ}\text{- H)}$to the carbonyl functional group via a cyclic transition state which is followed by the homolytic cleavage of $\mathrm{Î\pm }-Cand\mathrm{β}-C$ . This results in the formation of a neutral alkene and an enol radical cation. The peak of enol radical cation is observed at$\frac{\text{m}}{\text{z}} \text{=} \text{44}$ .

(b). The mechanism of McLafferty rearrangement of $\text{3}-\text{methylhexan}-\text{2}-\text{one}$can be shown by the transfer of hydrogen from the gamma position $\text{(}\mathrm{γ}\text{- H)}$to the carbonyl functional group via a cyclic transition state which is followed by the homolytic cleavage of role="math" localid="1664864445832" $\mathrm{Î\pm }-Cand\mathrm{β}-C$ .This results in the formation of a neutral alkene and an enol radical cation. The peak of enol radical cation is observed at $\frac{\text{m}}{\text{z}} \text{=} 72$.

(c). The mechanism of McLafferty rearrangement of $4-\text{methylhexan}-\text{2}-\text{one}$ can be shown by the transfer of hydrogen from the gamma position$\text{(}\mathrm{γ}\text{- H)}$ to the carbonyl functional group via a cyclic transition state which is followed by the homolytic cleavage of role="math" localid="1664864328002" $\mathrm{Î\pm }-Cand\mathrm{β}-C$.This results in the formation of a neutral alkene and an enol radical cation. The peak of enol radical cation is observed at$\frac{\text{m}}{\text{z}} \text{=} 58$ .