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HOMEWORK 9 Chapter 9 Substitution Reactions of Alkyl Halides 1) What is the nucleophile in the reaction shown below?

A) I B) II C) III D) IV E) V 2) Which of the following is not a nucleophile? A) CH3NH2 B) PH3 C) +CH3 D)

E)

3) Which of the following best describes the carbon-chlorine bond of an alkyl chloride? A) nonpolar; no dipole B) polar; δ+ at carbon and δ- at chlorine C) polar; δ- at carbon and δ+ at chlorine D) ionic E) none of the above

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4) Which of the following is not normally considered to be a nucleophile? A) NH3 B) NH2CH3 C) D) CH3CH2+ 5) Give the mechanism including the transition state.

6) Identify the alkyl halide that reacts the fastest in a SN2 reaction. A) 2-chloro-2-methylpropane B) 2-chlorobutane C) 1-chlorobutane D) chloromethane 7) Identify the alkyl halide that reacts the fastest in an SN2 reaction. A) 1-chloropropane B) 1-bromopropane C) 1-fluoropropane D) 1-iodopropane 8) Identify the strongest nucleophile in an SN2 reaction. A) isopropoxide ion B) tert-butoxide ion C) ethoxide ion D) tert-pentoxide ion

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9) Which of the following are the substitution products of the reaction shown below? CH3CH2Br + -OH → ? A) CH3CH2BrH+ + O- B) HOCH2CH2Br C) CH3CH2OH + Br- D) CH2 CH2 + Br- + H2O E) CH2 CHBr + H2O 10) Which of the following alkyl halides gives the slowest SN2 reaction? A) CH3CH2Cl B)

C)

D)

E)

11) Assuming no other changes, what is the effect of doubling only the concentration of the alkyl halide in the above SN2 reaction? A) no change B) doubles the rate C) triples the rate D) quadruples the rate E) rate is halved

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12) Assuming no other changes, what is the effect of doubling both the alkyl halide and the nucleophile concentrations in the above reaction? A) no change B) doubles the rate C) triples the rate D) quadruples the rate E) rate is halved 13) Which of the following SN2 reactions is the fastest? A)

B) CH3CH2CH2I + HO- → CH3CH2CH2OH + I- C)

D) CH3CH2CH3Br + HO- → CH3CH2CH3OH + Br- E) CH3CH2CH2I + H2O → CH3CH2CH2OH + HI 14) Provide the major organic product(s) in the reaction below.

15) Provide the structure of the major organic product of the following reaction.

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16) Give the mechanism.

17) Provide the major organic product of the reaction below and a detailed, stepwise mechanism which accounts for its formation.

18) Provide the structure of the major organic products which result in the reaction below.

19)The specific rotation of optically pure (R)-sec-butyl alcohol is -13.52°. An optically pure sample of (R)-sec-butyl bromide was converted into the corresponding sec-butyl alcohol via an SN2 reaction. What is the specific rotation of the product, assuming 100% yield? A) -13.52° B) between 0° and -13.52° C) between 0° and +13.52° D) +13.52° E) zero

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20) What product results from the SN2 reaction between (R)-2-chloropentane and hydroxide? A) (R)-2-pentanol B) (S)-2-pentanol C) racemic pentanol D) 1-pentanol E) 3-pentanol 21) Draw the product for the following SN2 reaction.

22) Which of the following alkyl bromides is likely to undergo rearrangement by a 1, 2-methyl shift? A) benzyl bromide B) 2-bromo-3-ethylpentane C) 3-bromo-3-methylpentane D) 2-bromo-3, 3-dimethylpentane E) 3-bromo-2, 3-dimethylpentane