6. How would you prepare the following compounds, starting with cyclopentene and other reagents needed? a. Chlorocyclopentane b. Cyclopentanol

Question

How would you prepare the following compounds, starting with cyclopentene and other reagents needed?

a. Chlorocyclopentane

b. Cyclopentanol

Answer 1

Alkene to alkyl halide = use hydrogen halide HCl or HBr depending on which halide you want to appear

cyclopentene (HCl)—> chlorocyclopentane

the double bond becomes a single bond. One of the carbons touching where the double bond was will have the Cl attach to it since it becomes a positive carbocation and the other will get the extra H. Since this is a symmetrical ring with no other components we do not care which is which.

Alkene to alcohol = sulfuric acid with water or H3O+ (H+) catalyst with water (in general, water and acid)

cyclopentene (H2SO4/H2O)—> cyclopentanol

the double bond becomes a single bond. One of the carbons touching where the double bond was will attract the OH as a carbocation and the other location will pull in an H as a partial negative. Since this is a ring with no other components we don’t care which is which.