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GATE 2023 CY – Question 50

Organic Chemistry · Oxidation: Oxidation of alcohols involving metal and non-metal-based (chromium, manganese, DMSO, and hypervalent iodine) reagents. Peracid oxidation of alkenes and carbonyls. Alkenes to diols (manganese and osmium-based reagents), alkenes to carbonyls with bond cleavage (ozonolysis), and alkenes to alcohols/carbonyls without bond cleavage (hydroboration-oxidation). Asymmetric epoxidations (Sharpless and Jacobsen) and Sharpless asymmetric hydroxylation. · 2 marks · Multiple select

Product(s) formed in the given reaction sequence is(are)

Diagram for GATE 2023 CY question 50
  1. Structure A
  2. Structure B
  3. Structure C
  4. Structure D

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Show answer and explanation

Correct answer: (A) Structure A; (C) Structure C

Explanation

Bromine-water chemistry, including neighbouring carboxyl participation, sets the halohydrin stereochemistry. Base forms an alkoxide that closes by backside displacement to an epoxide, so the oxygen bridge and adjacent substituent relationships must match that sequence. The allowed enantiomeric epoxides are **A, C**; B has the wrong relative configuration and D remains a diol.