Question:
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Vicinal diols they undergo oxidation with periodic acid which results in the formation of aldehydes and ketones.
1,2- or vicinal diols are cleaved by periodic acid, HIO4, into two carbonyl compounds.
The reaction is  for 1,2-diols(vicinal diols).
The reaction occurs via the formation of a cyclic periodate ester (see image )
The products are determined by the substituents on the diol
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