See image — Alcohols Phenols and Ethers Chemistry Question

💡 Solution & Explanation

Concept: PCC (pyridinium chlorochromate) is a mild oxidizing agent that selectively oxidizes primary alcohols to aldehydes and secondary alcohols to ketones, but does NOT oxidize tertiary alcohols. It also does not over-oxidize aldehydes to carboxylic acids. Step 1: Identify the alcohol types in the substrate. - The -CH2OH group at C1 of the cyclohexane ring is a PRIMARY alcohol (the carbon bearing -OH is attached to one carbon, the ring carbon). - The -C(CH3)2OH group at C4 is a TERTIARY alcohol (the carbon bearing -OH is attached to three carbons: two methyl groups and the ring carbon). Step 2: Apply PCC reactivity rules. - PCC oxidizes the primary alcohol (-CH2OH) to an aldehyde (-CHO). - PCC does NOT oxidize the tertiary alcohol (-C(CH3)2OH) because tertiary alcohols lack a hydrogen on the carbon bearing -OH, making oxidation impossible under these mild conditions. Step 3: Determine the product. - The primary -CH2OH is oxidized to -CHO. - The tertiary -C(CH3)2OH remains unchanged. - Product: cyclohexane ring with -CHO at C1 and -C(CH3)2OH at C4, which matches option (b). Why other options fail: - (a) Shows an elimination product (isopropylidene formation), which PCC does not cause. - (c) Shows a carboxylic acid (-CO2H), which PCC cannot produce (it stops at aldehyde stage and does not oxidize tertiary alcohols). - (d) Shows a ketone at the ring carbon (C1), which would require oxidation of a secondary alcohol; here C1 bears a -CH2OH (primary), so the ring carbon itself is not oxidized to a ketone. Therefore, the correct answer is B.