Oxymercuration-demercuration of compound 1 affords the

Chapter 14, Problem 14.69

(choose chapter or problem)

Oxymercuration-demercuration of compound 1 affords the expected hydration product 2 in 96% yield. In contrast, oxymercuration-demercuration of compound 3 results in only a minor amount of the normal hydration product. Instead, compounds 7 and 8 are formed (J. Org. Chem. 1981, 46, 930939). It is believed that the initial product of oxymercuration (compound 4) undergoes an intramolecular epoxide-opening step, giving two possible cyclic compounds, 5 and 6. This step is likely catalyzed by the interaction between the epoxide group and Hg(OAc)2, which functions as a Lewis acid. (a) Draw the structure of 2. (b) Draw the structures of 4, 5, and 6 and show a mechanism for the conversion of 4 S 5 as well as 4 S 6. (c) Explain why the product distribution is so different for epoxyalkenes 1 and 3. 1 O 3 O 1) Hg(OAc)2, H2O 2) NaBH4 2 Hg(OAc)2 H2O 4 NaBH4 O OH O OH 5 6 7 8