Which reagent oxidizes a secondary alcohol to a ketone?

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Multiple Choice

Which reagent oxidizes a secondary alcohol to a ketone?

The key idea is choosing an oxidant that converts a secondary alcohol to a ketone without pushing further to carboxylic acids or other products. PCC (pyridinium chlorochromate) is a mild Cr(VI) oxidant that does exactly this: it oxidizes secondary alcohols to ketones under relatively gentle conditions and typically doesn’t over-oxidize primary alcohols to acids. That makes it reliable for forming a ketone from a secondary alcohol. In contrast, Jones oxidation is harsher. It will oxidize secondary alcohols to ketones as well, but it’s strong enough to push primary alcohols all the way to carboxylic acids, which is not always what you want. Ozonolysis isn’t about oxidizing alcohols at all—it cleaves alkenes. Permanganate oxidation is a strong, less selective oxidant and can over-oxidize or lead to other pathways, reducing selectivity for stopping at a ketone from a secondary alcohol. So PCC is the best choice here because it cleanly gives the ketone from a secondary alcohol under mild, selective conditions.

The key idea is choosing an oxidant that converts a secondary alcohol to a ketone without pushing further to carboxylic acids or other products. PCC (pyridinium chlorochromate) is a mild Cr(VI) oxidant that does exactly this: it oxidizes secondary alcohols to ketones under relatively gentle conditions and typically doesn’t over-oxidize primary alcohols to acids. That makes it reliable for forming a ketone from a secondary alcohol.

In contrast, Jones oxidation is harsher. It will oxidize secondary alcohols to ketones as well, but it’s strong enough to push primary alcohols all the way to carboxylic acids, which is not always what you want. Ozonolysis isn’t about oxidizing alcohols at all—it cleaves alkenes. Permanganate oxidation is a strong, less selective oxidant and can over-oxidize or lead to other pathways, reducing selectivity for stopping at a ketone from a secondary alcohol.

So PCC is the best choice here because it cleanly gives the ketone from a secondary alcohol under mild, selective conditions.

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