Q8(a)(i). Products X and Y in four reagent problems
Write the products X/Y in the following chemical transformations: I. 1-phenyl-1,2-dihydronaphthalene with MCPBA gives X. II. 1,4-dihydronaphthalene with OsO₄ gives X, which with NaIO₄ gives Y. III. 3-hydroxybutanoic acid with BH₃/THF gives X. IV. Cyclohexene with CrO₃–pyridine in CH₂Cl₂ gives X. [structures given in the paper]
Answer in brief
I. trans-3,4-epoxide of 1-phenyl-1,2-dihydronaphthalene; II. X = cis-tetralin-2,3-diol, Y = benzene-1,2-diacetaldehyde; III. butane-1,3-diol; IV. cyclohex-2-en-1-one.
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CoversMCPBA epoxidationOsO4 dihydroxylationNaIO4 cleavageborane reduction of carboxylic acidCollins reagentallylic oxidation
All parts of Question 8
- 8(a)(i) Products X and Y in four reagent problems15 marks
- 8(a)(ii) 2-Methylbut-1-ene with diborane5 marks
- 8(b)(i) C₉H₁₈O with a single ¹H NMR line10 marks
- 8(b)(ii) Two UV bands of acetone5 marks
- 8(c)(i) ¹H NMR spectrum of methyl propenoate10 marks
- 8(c)(ii) Two carbonyl bands of chloroacetone5 marks