SN1/SN2 Practice Problems PDF
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These are practice problems covering SN1 and SN2 reactions in organic chemistry. The problems involve drawing product structures and mechanisms, including stereochemistry. The problems focus on identifying which method will react faster, judging based on the leaving group, etc. The questions range from basic to more challenging, providing practice for students.
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# SN1/SN2/E1/E2 Practice Problems 1. Draw the structure of the major organic product of each reaction shown. If no reaction, write NR. Do not forget stereochemistry. - (a) Br + NaN3 -> CH3CN, NR, OH is a poor LG - (b) OH + NaBr -> Pyr, OH, 2O-5-CH3, By - (c) OH + H3C-S-CI -> NaBr, Br,...
# SN1/SN2/E1/E2 Practice Problems 1. Draw the structure of the major organic product of each reaction shown. If no reaction, write NR. Do not forget stereochemistry. - (a) Br + NaN3 -> CH3CN, NR, OH is a poor LG - (b) OH + NaBr -> Pyr, OH, 2O-5-CH3, By - (c) OH + H3C-S-CI -> NaBr, Br, Br - (d) Br + NaOH, NaBr (excess), acetone -> OH, Br, no SN2 at sp2 carbon - (e) H3C Br + NaOH, assume SN2 -> OH, Br - (f) + Na + Br -> elimn - (g) Br + CH3ONa, heat, anti (180) -> Br, DH - (h) Br + NaOCH3, Assume Elimination -> + major - (i) Br + Nal, acetone -> -CH3, CH2CH3 We'll discuss in class 2. Show what nucleophile/electrophile pair you will use to synthesize the following compounds: - (a) OH - (b) CH3, OCH3 - (c) NH2 - (d) O We'll discuss in class. 3. Write a detailed reaction mechanism for the following reactions: - CH2Br + CH3OH, heat -> CH2 + CH3, H3CO CH3 + + OCH3 We'll discuss in class. 4. Circle the better nucleophile in each pair: - (a) OH vs H2O, **OH**. Species w/ neg charge better. - (b) SH vs H2S, **SH** - (c) NH2 vs OH, **NH2**, O > N Electroneg, less willing to give up e, EN more impt than size, across period. - (d) (CH3CH2)3P vs (CH3CH2)2S, **(CH3CH2)3P** - (e) I vs Br, **I**, Size I >Br - (f) (CH3CH2)3P vs (CH3CH2)3N, **(CH3CH2)3P**, size P > N 5. Circle the compound that will react faster via the indicated pathway. - (a) Br vs Cl, **Br**, better LG, SN2. - (b) Br vs Br, **Br**, less hindered, SN2. - (c) Br vs Cl, **Cl**, 2° more stable, SN1. - (d) Br vs Cl, **Cl**, better LG, SN1. - (e) Br vs Br, **Br**, resonance stabilized, SN1. # SNI - SN2 Key 1. OH, Will NaBr/acetone work? Explain. No, OH is a poor LG. See notes re use of sulfonates to make better LG. 2. H3C Br, NaOH, acetone -> OH, H3C, inversion. 3. CH3, Br + KOCH(CH3)3, HOC(CH3)3, heat -> + , favors elimn 4. CH3, Br + KOCH(CH3)3, HOC(CH3)3, heat -> + , major.
