We have covered several oxidants that use a multi-valent atom (Cr, Cl, S, or I) as their active species, going from a higher oxidation state before the oxidation to a lower oxidation state after oxidizing the alcohol. Draw the structure of the following atoms, before and after the oxidation of an alcohol to a ketone or aldehyde. How many bonds to oxygen does each atom have before and after the oxidation?
(a) The Cr in chromic acid
(b) The Cl in sodium hypochlorite
(c) The S in the Swern oxidation
(d) The I in the DMP reagent
(e) The carbinol C in the alcohol that is oxidized?