Mercury acetate cyclopropane ring

Oxymercuration of simple alkyl- and acyl-substituted cyclopropenes generally results in ring opening.Addition of mercury(II) acetate to 3-methyl-3-phenylcyclopropene, however, gave a low yield of a cyclopropane containing organomercury compound (15-20%), which was converted into an isomeric mixture of 1 -methoxy-2-methyl-2-phenylcyclopropanes by reduction with lithium aluminum hydride. Reaction of 5 with mercury trifluoroacetate in methanol and then sodium hydroxide led predominantly to one cylopropane. ... 

The mercury derivatives of bicyclic and monocyclic cyclopropanes underwent ready addition across electron-deficient C —C double bonds. This addition reaction was performed with isolation of the mercury intermediate, e.g. 6, giving and often without isolation of the mercury intermediate giving and 9 directly. Depending on the solvent used (MeOH or HOAc) either methoxide or acetate acted as the nucleophile in the ring-opening reaction. 

When the bicyclo[3.1.0]hexane rather than the bicyclo[4.1.0]heptane system was submitted to electrophilic ring opening with mercury(II) acetate, cleavage of both the inside and the outside cyclopropane bond was observed. The ratio of products 16 and 17 depended on the substituent in position 3. 

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