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172 Chapter 9 FURTHER REACTIONS OF ALCOHOLS AND THE CHEMISTRY OF ETHERS 30. The products are shown above. Except for part (a), only the mechanisms and intermediates will be presented here. H Primary carbon H This combination, together with + (a) the strong nucleophile I⁻, suggests H an SN2 mechanism. good leaving group CH₃CH₂CH₂I + H₂O H-Br: Primary carbon again H (b) SN2 mechanism, again :Br: H H-1: + OH OH₂ + (c) H H H Secondary carbon this time; mechanism follows from protonated secondary alcohols CH₃CH₂ H Cl: CH₃CH₂ CH₂CH₃ + + (d) C OH C OH₂ C CH₃CH₂ CH₃CH₂ CH₂CH₃ CH₂CH₃ CH₃CH₂ CH₂CH₃ Tertiary carbon: 31. In each case the species are written in an order reflecting a sequence of rearrangement steps. Rearrange- ments do not occur to an equal extent under all circumstances. Structures to the right are generally most stable. (a) + CH₃CHCH₃ + (Similar to rearrangement of 2,2-dimethyl-1-propanol in Section 9-3.) (b) CH₃CHOH₂CH₃, CH₃CHCH₃ (c) CH₃CH₂CHCH₃ (d) (CH₃)₂CHCH₂OH₂, (CH₃)₃C⁺ (e) + (CH₃)₂CCH(CH₃)₂ Some mechanism arrows are included on the following page to help you find your way.