Hydroxy cyclobutenones rearrangement

Reactions of4-hydroxy-2-cyclobutenones 364 with (diacetoxyiodo)benzene in 1,2-dichioroethane at reflux afford 5-acetoxy-2(5//)-furanones 365 as rearranged products (Scheme 3.146) [466], The formation of these products is explained by ring cleavage in the hypervalent iodine intermediate 366 foiiowed by recycliza-tion of the resulting acyl cation 367 with the carbonyl oxygen (Scheme 3.146). In a similar procedure,... 

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