課程名稱︰有機化學乙
課程性質︰化工系 必修
課程教師︰羅禮強
開課學院:工學院
開課系所︰化工系
考試日期(年月日)︰2018.10.18
考試時限(分鐘):110分鐘
試題 :
1. Isotope labeling is an important tool in the study of reaction mechanisms. How will you selectively deuterate the specified hydrogen atom, indicated by an arrow, in the following compound? Use equations to clarify your answer and briefly explain your rationale. (4 points)
https://i.imgur.com/xXY5VJK.jpg
2. You are planning to purify an impure sample of benzoic acid (C6H5CO2H), known to be contaminated naphthalene (C10H8). Propose a strategy for purifying this sample, making use of acid-base principles, using equations to further clarify your answer. (6 points)
3. Complete the following acid-base reactions. Draw all non-bonding electrons and show electron flow with curved arrows. (a) CH3COOH+(CH3CH2)3N. (b) C2H5OH+CH3Li. and (c) (CH3)3COH+H3O+.(12 points)
4. Draw the bond-line structural formula corresponding to the most stable conformation of the following compounds: (a) cis-1,4-dimethyleyclohexane and (b) trans-2-tert- butylcyclohexanol. (8 points)
5. Calculate the index of hydrogen deficiency for the following compounds: (a) C9H18N2.(b) C8H10. (c) C21H30O5, and (d) C8H3Br5O2. Show your calculations. (8 points)
6. Name the following groups or compounds(including stereochemistry).(16 points)
https://i.imgur.com/gH7DrD4.jpg
7. Draw Fischer projection formulas for the following compound. Designate the R/S configuration at each stereocenter in the structure, and show how they are determined. (8 points)
https://i.imgur.com/jRJpj5m.jpg
8. Use Newman projection viewed through the C-2-C-3 bond to show the most stable conformation of 3-bromo-2-methylpentane. (6 points)
9. Identify the relationship between the following pairs of structures. (8 points)
https://i.imgur.com/mYFawzT.jpg
10. A compound X with the molecular formula C6H10 is optically active. On catalytic hydrogenation X is converted to Y (C6H12) and Y is optically inactive. Propose structures for X and Y, and show how you deduce your answers. (8 points)
11. Draw a hypothetical free-energy diagram for an SN2 reaction shown below. Assume it is exergonic, and you don't need to provide specific values. Please label the following on the diagram: (a) ΔG0. (b) ΔG** and (c) transition state. (10 points)
CH3I + OH- ——> CH3OH + I-
12. What is the percent composition of a mixture of compound Z that shows a specific rotation [a] 25/D= +20,where the pure enantiomer has a reference value of [a] 25/D = +25?(6 points)