課程名稱︰有機化學一
課程性質︰化學系大二必修
課程教師︰羅禮強
開課學院：理學院
開課系所︰化學系
考試日期（年月日）︰2021/1/14
考試時限（分鐘）：110min
試題 :
1. Explain the relative distribution of products below using energy diagram for
the hydrogen abstraction step that leads to each product. In energy diagrams for
the two pathways, show the relative energies of the transition states and of th
e alkyl radical intermediates that results in each case.
https://i.imgur.com/eadYKyV.jpg
2. Consider the monochlorination of
2-methylbutane.
(a) Assuming that the product mixture was subjected to fractional distillation,
which fractions, if any, would show optical activity?
(b) Could any of these fractions be resolved, theoretically, into enantiomers?
(c) Could the compounds of each fractions from the distillation be identified on
the basis of H-NMR spectroscopy? What specific characteristics in a H-NMR spect
rum of each fraction would indicate the identity of the compound(s) in that frac
tion?
3. How is the endo-/exo- position of a bridged bicyclic compound defined? Use th
e two methyl groups of 2,2-dimethylbicyclo[2,2,1]heptane as an example.
4. Briefly describe the following terms:
(a) conjugated system,
and (b) endiyne antibiotics.
5. What integral values would you expect for signals in H-NMR spectrum for each
of the following compounds?
https://i.imgur.com/wnikLMZ.jpg
6. When 1-hexene reacts with NBS, two products with the formula C6H11Br are obta
ined. What are these two products? Provide a mechanism to account for this obser
vation.
7. What is the major product obtained from each of the following reactions?
https://i.imgur.com/oLxBaTA.jpg
8. Write a mechanism that accounts for the following reaction. Note that the hyd
rogen atom bonded to tin in tributyltin hydride is readily transferred in radica
l mechanisms, and AIBN is a radical initiator.
https://i.imgur.com/T5AbQB9.jpg
9. Which of the following compounds would have a larger coupling constant (J_a,b
). Explain your answers.
https://i.imgur.com/G0ITs6x.jpg
10. Which diene and dienoplile would you employ to synthesize the following comp
ounds?
https://i.imgur.com/igQDugh.jpg
11. Explain why polyunsaturated fatty acids are much prone to autoxidation.
12. Briefly exhaling how you might distinguish between the following substances
by comparing their following H-NMR spectra.
https://i.imgur.com/Sa6aFEh.jpg
13. Deduce the structure of the following compounds based on the spectral data p
rovided. Explain your answers.
(a) Compound P, C4H8O. H-NMR δ 9.76(s, 1H), 2.37(q, 2H), 1.64(m, 2H), 0.97(t, 3
H).
(b) Compound Q, C8H16. The broad-band proton decoupled C-13 spectrum of Q shows
six signals at δ 135(CH), 130(C), 33(C), 32(CH3), 27(CH3), 20(CH3).
(c) Compound X, C7H7Br. H-NMR δ 7.39(d, 2H), 7.06(d, 2H), 2.31(S, 3H).
(d) Compound Y C6H10O. The broad-band proton decoupled C-13 spectrum of Y shows
signals at δ 212 (C), 42(CH2), 27(CH2), 25(CH2).
(e) Compound Z, C10H12O. H-NMR δ 9.90(s, 1H), 7.78(d, 2H), 7.34(d, 2H), 3.15(m,
1H), 1.25(d, 6H); C-13 NMR δ 192(CH), 155(C), 134(C), 130(CH), 127(CH), 36(CH)
, 24(CH3).