Silver acetate cycloalkenes

Stereoselective cis-dihydroxylation of the more hindered side of cycloalkenes is achieved with silver(I) or copper(II) acetates and iodine in wet acetic acid (Woodward gly-colization J.B. Siddall, 1966 L. Mangoni, 1973 R. Criegee, 1979) or with thallium(III) acetate via organothallium intermediates (E. Glotter, 1976). In these reactions the intermediate dioxolenium cation is supposed to be opened hydrolytically, not by Sn2 reaction. 

Instead of silver salts, the somewhat cheaper but more toxic thallium(I) acetate may be used [410], Examples of syn and anti hydroxylations of cycloalkenes are shown in equations 80-82 [131, 242, 244, 410, 782, 900, 905, 952]. 

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