For oxidizing alcohols, several oxidants – each with a multivalent central atom as the active species – can be used. When Dess-Martin periodinane (DMP), with I as the multivalent atom is used, how many bonds to oxygen atoms does each central multivalent atom have just before and immediately after the oxidation respectively?
4 – before, 2 – after
Without going into an actual reaction, let us take a look at only the DMP reagent that gets reduced:
4 bonds with oxygen before and 2 bonds with oxygen post reduction.