24. Malonic ester (diethyl malonate) is treated successively with sodium ethoxide (1 eq.), ethyl bromide, potassium tert-butoxide, isobutyl chloride, hot aqueous NaOH, HCl, and heat. What is the final product?
(A) 4-Ethyl-2-methylpentanoic acid
(B) 6-Methylheptanoic acid
(C) 2-Ethyl-3-methylpentanoic acid
(D) 2-Ethyl-4-methylpentanoic acid
(E) Ethylisobutylmalonic acid

1. Which of these dienes is the most reactive in the Diels-Alder reaction? (A) 1,3-Butadiene (B) 1,4-Pentadiene (C) 2,3-Dimethyl-1,3-butadiene (D) 1,2-Butadiene (E) 1,4-Cyclohexadiene

2. Which of the following is      not      true concerning the strength of a nucleophile? (A) Nucleophilicity may not parallel basicity. (B) Negatively charged nucleophiles are always more reactive than their conjugate acids. (C) The greater the strength of a nucleophile, the faster an Sₙ2 reaction will occur. (D) Strong bases are always good nucleophiles (E) None of these answer choices are correct.

3. Why is sodium methoxide      not      used in the Claisen condensation of ethyl acetate? (A) The methoxide is a weaker base than the ethoxide which is used. (B) sodium methoxide is more difficult to prepare than sodium ethoxide. (C) The methoxide would abstract a proton from the ethyl group of the ester. (D) Use of sodium methoxide would result in transesterification. (E) sodium methoxide can be used as well as sodium ethoxide.

4. Which of these is      not      a reversible process? (A) Base-promoted ester hydrolysis (B) Acid-catalyzed ester hydrolysis (C) Aldol addition (D) Claisen condensation (E) Acetal formation

5. A compound has the molecular formula, C₆H₁₂O₂. Its IR spectrum shows a strong absorption band near 1740 cm⁻¹; its ¹H NMR spectrum consists of two singlets, at δ 1.2 and 3.6 ppm. The most likely structure for this compound is: (A) Isopropyl propionate (B) Propyl propionate (C) Ethyl isobutyrate (D) tert-Butyl acetate (E) Methyl pivalate

6. Which of the following terms correctly describes these compounds listed below? (A) conformational isomers (B) not isomers (C) stereoisomers (D) constitutional isomers (E) enantiomers

7. Which of the following predictions of δ value and splitting pattern of the labeled protons in ¹H NMR (CDCl₃) is true? (A) Hₐ (2.5 ppm, triplet) (B) Hb (3.1 ppm, triplet of triplet) (C) Hc (3.1 ppm, triplet of triplet) (D) Hd (2.2 ppm, triplet of doublet) (E) He (2.0 ppm, singlet)

8. List of the following compounds in order of increasing reactivity in a Sₙ1 reaction. (i) MeI (ii) nBuBr (iii) tBuI (iv) iBuBr (v) iBuI (A) i ＜ ii ＜ v ＜ iv ＜ iii (B) i ＜ ii ＜ iv ＜ v ＜ iii (C) iii ＜ v ＜ iv ＜ ii ＜ i (D) iii ＜ iv ＜ v ＜ ii ＜ i (E) iii ＜ i ＜ iv ＜ ii ＜ v

9. Which of the following compound is aromatic? (A) (B) (C) (D) (E)

10. Which of the following amine can be resolved into enantiomers? (A)(B) (C) (D) (E)

115年 - [無官方正解]115 國立臺灣大學_ 碩士班招生考試試題：有機化學(A)#137731

114年 - 114 台灣聯合大學系統_碩士班招生考試_化學類：有機化學#127002

113年 - 113 台灣聯合大學系統_碩士班招生考試試題_化學類：有機化學#122395

112年 - 112 台灣聯合大學系統_ 碩士班招生考試試題：有機化學#138486

112年 - 112-2 嘉南藥理大學_轉系招生藥學系考試試題_四技一年級：有機化學#119239

111年 - [無官方正解]111台灣聯合大學系統_ 碩士班招生考試試題：有機化學#138494

110年 - 110-2 嘉南藥理大學_轉系招生藥學系考試試題：有機化學#120872

110年 - 110 國立臺北科技大學_碩士班招生考試_分子科學與工程系有機高分子碩士班(甲組)：有機化學#110883

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

110年 - 110 國立清華大學碩士班考試入學試題_生命科學院/乙組(化學與生醫工程組):有機化學#104958