未分類

68. Which of the compounds below undergoes solvolysis in aqueous ethanol most rapidly?(A) Cyclohexyl

69. Which of the following E, Z designation are incorrect? (A) AB (B) BC (C) CD (D) AD (E) AC

70. Provide structure for compound A in the following reaction scheme:(A) A (B) B (C) C (D) D(E) Non

71. What is the major organic product of the following sequence of reactions?

72. What product would you obtain from Claisen condensation of ethyl propanoate?(A) Ethyl 2-ethyl-3-

73.What is the major organic product of the reaction shown below? (A) Ethyl benzoate (B) Phenyl prop

74. Which of the following reactions has a mechanism that involves the formation of a cyclic interme

75. Which of the following substituents would have the lowest Cahn-Ingold-Prelog priority?(A) -CH2OH

76. Which sets of reagents would give the correct product for this reaction? (A) Hg(OCOCF3)2 in MeOH

77. The Frost circle can be used to reproduce the molecular orbital energies of a cyclic polyene. Wh

78. What is the product of acid-catalyzed hydrolysis of the ketal shown below?？

79. What is the product in the following reaction sequence? (E) None of the above

80. What is the major product for the following reaction?

1. Consider the resonance of compound A, which one is not its resonance form? (A) (B) (C) (D) (E)

2.Which of the following compounds is not an aromatic compound?(A) (B) (C) (D) (E)

3.For each compound below, which one will give 3 signals in its normal, broadband decoupled 】JC NMR

4.What will be the major product of the following reaction? (A) (B) (C) (D)  (E) None of the above

5.Which of the following reactions would not show primary kinetic isotope effect? (A) (B) (C) (D) (E

6. When bromide AK is treated with NaOEt， four2- butene are possible products.  (A) AK-aand AK-b are

7.Solvent isan important factor in the nucleophilic reaction. We classified solvent into several cat

8.Consider the spectrum illustrated below.Which of the following structures will be best for this sp

9.The average mass of a boron atom is 10.81.If you were able to isolatea single boron atom, whatisth

10. Which of the statements below correctly describes the chair conformations of trans-1,4-dimethylc

11. Which is a measure of the randomness of a system?j(A) entropy(B)enthalpy(C)free energy(D)halogen

12. Which of the following species is the least nucleophilic?j(A) H20(B)BF3 (C)(CH3)3N(d)CH3O- (e)CH

 3690   首頁 上一頁 44 45 46 47 48 49 50 51 52 53 下一頁 尾頁