110年 - 110 國立清華大學碩士班考試入學試題_部分研究所:有機化學#104992

1. The simplest amino acid is (A) Alanine (B)Serine (C) Glycine (D) Valine

2. In a Merrifiled solid phase peptide synthesis, if there are 5 steps and each goes in 90% yield, what is the overall yield? (A)18% (B)45% (C) 59% (D)90%

3. Esters and amides are the most easily made by nucleophilic acyI substitution reactions on: (A) alcohols (B)acide anhydrides (C) carboxylates (D) carboxylic acids(E) acid chlorides

4. An organic compound A is formed by the reaction of ethylmagnesium iodide with a substance B, followed by the treatment with dilute aqueous acid. Compared A does not react with pyridinium chlorochromate in dichloromethane. Which one the following is a possible candidate for B? (A) CH₃CHO (B) CH₃CH₂OH (C) CH₃CH₂COCH₃(D) HCO₂CH₃

5. Vulcanization is a process to strengthen natural rubber by crosslinking polymer chains with what element? (A) sodium (B)titanium (C)sulfer (D) phosphorus(E)aluminum

6. Epoxide undergoes ring-opening reaction with water to generate (A) glycol (B)glyoxal (C)ester alcohol (D)none of above

複選題

7. For isobutanol: (A) it is a primary alcohol (B) it is a constitutional isomer of cyclobutanol (C) it shows a characteristics absorption at in IR spectrum (D) it shows four carbon signals in the NMR spectrum.

8. Which one of following structures has the lowest pKa?(A)(B)(C)(D)(E)

9. Which description about the frontier molecular orbital theory is False? (A) HOMO is an acronym for highest occupied molecular orbital. (B) Antibonding molecular orbitals are higher in energy than the isolated atomic orbitals from which they made. (C) The LUMO of 1,3-butadiene has one node. (D) The HOMO of allyl anion has one node. (E) The thermal [2+2] cycloaddition of two ethylenes to give cylobutane is a symmetry-forbidden reaction.

10. Which of following addition reactions of alkenes occur specifically in an anti- fashion: (A) Dihydroxylation using OsO₄, H₂O₂ (B) Addition of Br₂(C) Hydroboration-oxidation (D) Hydrogenation using H₂-Pt

11. The conversion of 2-pentanone to butanoic acid is best accomplished with: (A) I₂, NaOH (B) NaBH₄ (C) CrO₃ (D) Ag₂0

12. A molecule has three degrees of unsaturation. In this molecule there would be (A) three rings (B) three double bonds (C) two rings and one double bond (D) one ring and two double bonds (E) any of the above

13. What is the IUPAC name of the following compound?
(A)( E )-3-methylpent-3-ene (B) (Z)-3-methylpent-3-ene (C) ( E )-3-methylpent-2-ene (D) (Z)-3-methylpent-2-ene

複選題
14. Which pair listed below is a Lewis acid-base pari? (A) 2,6-di-tert-butylpyridine + HCI (B) BF₃ + ether (C) Benzoic acid + NaOH (D) tert-butyl chloride + benzene (E) acetone + H₂ SO₄

15. Which statement is correct for the reaction shown below?
1-chloro-2,4-dinitrobenzene + NaOH → 2,4-dinitrophenol (A) This reaction is an electrophilic aromatic substitution. (B) 'This reaction is a SN2 substitution. (C) This reaction is a nucleophilic aromatic substation. (D) Substituted benzyne is the reaction intermediate.

16. Assuming the ionization energy of a hydrogen atom is E, estimate the 4f orbital energy for a Li2+ cation: (A) 3E/4 (B)-3E/4 (C) 9E/16 (D) -9E/16 (E) E/4

17. Which of the following compounds is a suitable base to prepare ester enolate of ethyl acetate? (A) Lithium diisopropylamide(B) Pyridine (C) Diisopropyl amine (D) Pyrrolidine

18. In a solution of aspartic acid (pKa=7.4) adjusted to a pH of 2.74, (A) the ration of asparate to asparatic acid is 10 to 1. (B) the ration of asparate to asparatic acid is 100 to 1. (C) the ration of asparate to asparatic acid is 1000 to 1. (D) the ration of asparate to asparatic acid is 1 to 10. (E) the ration of asparate to asparatic acid is 1 to 100.

19. Addition of Br₂ to ( E )-hex-3-ene produces_________. (A) A meso dibromide. (B) A mixture of enantiomeric dibromides which is optically active. (C) A mixture of enantiomeric dibromides which is optically inactive. (D) (Z)-3,4-dibromo-3-hexene. (E) ( E )-3,4-dibromo-3-hexene.

20. Which of the following compounds has the most negative heat of hydrogenation? (A) 14-hexadiene (B) 1,5-hexadiene (C) 1,2-hexadiene (D) 1,3-hexadiene (E) hex-1-ene

21. Which compounds is the most stable? (A)1,4-pentadiene (B) trans-1,3-pentadiene (C) trans-1,4-pentadiene (D) cis-1,4-pentadiene

22. The Diels-Alder reaction is a concerted reaction； this means: (A) A mixture of endo and exo products is formed. (B) All bond making and bond breaking occurs simultaneously. (C) The products contain rings. (D) The reaction follows Markovnikov's rule. (E) The reaction is highly endothermic.

23. Which of the statements below correctly describes an achiral molecular? (A) The molecule has a non-superimposable mirror image. (B) The molecule exhibits optical activity when it interacts with plane-polarized light. (C) The molecule has an enantiomer (D) The molecule might be meso form

24. The reaction conditions to carry out the production of cyclopentene using bromocycylpentane as the starting material would be: (A) KOH, CH₃CH₃OH (B) H₂SO₄, THF (C) H₂O₂,OH (D) Hg(OAc)₂, H₂O

25. Which is the reaction major product when benzene reacts with propene in the presence of HF? (A) propylbenzene (B) iso propylbenzene (C) 3-propylbenzene (D)1- propylbenzene

110年 - 110 國立清華大學碩士班考試入學試題_部分研究所:有機化學#104992

試卷資訊

選擇題 (25)

申論題 (0)