(h)The unimolecular mechanisms SN1 and E1 involve the formation of carbocation intermediates.(i)Rearrangements are possible when carbocations are intermediates in a reaction. Thus reac-tions occurring by the SN1 and E1 mechanisms are most likely to have a rearranged carbonskeleton.(j)Iodide is a better leaving group than bromide, and alkyl iodides will react faster than alkylbromides by any of the four mechanisms SN1, SN2, E1, and E2.8.30(a)Cyclopentyl cyanide can be prepared from a cyclopentyl halide by a nucleophilic substitutionreaction. The frst task, therefore, is to convert cyclopentane to a cyclopentyl halide.An analogous sequence involving cyclopentyl bromide could be used.(b)Cyclopentene can serve as a precursor to a cyclopentyl halide.Once cyclopentyl bromide has been prepared, it is converted to cyclopentyl cyanide bynucleophilic substitution, as shown in part (a).(c)Reaction of cyclopentanol with hydrogen bromide gives cyclopentyl bromide. Then
This is the end of the preview.
access the rest of the document.