CHEM 2443 Practice Exam 3 2024 PDF

## CHEM 2443 Practice Exam 3 **(Questions 1-12 are 3 points each)** ### 1. What is the relationship between the following compounds? * CH3 * CH3 and CH3 * CH3- * A) superimposable without bond rotation * B) constitutional isomers * C) conformational isomers * D) diastereomers * **E...

## CHEM 2443 Practice Exam 3 **(Questions 1-12 are 3 points each)** ### 1. What is the relationship between the following compounds? * CH3 * CH3 and CH3 * CH3- * A) superimposable without bond rotation * B) constitutional isomers * C) conformational isomers * D) diastereomers * **E) enantiomers** * **Non-superimposable mirror images.** ### 2. What is the relationship between the structures shown below? * Br * Br and * * Br * Br * **A) enantiomers** * B) diastereomers * C) configurational isomers * D) identical compounds * E) constitutional isomers ### 3. For the following reaction, one major and two minor products of the four structures shown below have been isolated. Indicate the product that has not been isolated. * Br * H * CH3 * CH2CH2ONa * CH2CH2OH * major and * minor * products * H * H * H * (Primarily E2, minor SN2) * 1) * 2) * major * 3) * 4) * minor * A) 1) * B) 2) * C) 3) * **D) 4)** ### 4. Predict the major product formed in the following reaction? * CH3 * NaSH * acetone * major * product * SH * R * Br * SN2 * CI * CI3 * H * CH3 * CH3 * 1) * R * SH * 2) Racemic * SH * 3) * SH * 4) * CH3 * A) 1) * B) 2) * **C) 3)** * D) 4) ### 5. What is the major product formed in the following reaction? * Br * Br * + CH2CH2ONa * Ethanol * major * product * E2 * 1) * 2) * 3) * 4) * 5) * A) 1) * B) 2) * **C) 3)** * D) 4) * E) 5) ### 6. What is the major product formed in the following reaction? * Br * H * H * Br * Ph * H * Ph * CH3 * H * C (CH3)3 * NaOCH3 * methanol * major * product * Ph * CH3 * H * C (CH3)3 * Ph * Ph * 1) * 2) * 3) * 4) * 5) * A) 1) * B) 2) * C) 3) * D) 4) * **E) 5)** ### 7. What is the major product of the following reaction? * Et * Br * * H * NaOCH3 * HOCH3 * H * Et * H * Et * OMe * H * Et * H * Et * C * OMe * B * Et * C * D * H * H * Et * A) A * B) B * C) C * **D) D** * E) E ### 8. For the given reaction, predict the major and minor products (no carbocation rearrangement). * OH * NaBr * H2O, * major and * minor * products * Br * 1) * 2) * minor * 3) * 4) * major * Br * A) 1 major, 2 minor * B) 3 major, 4 minor * C) 1&2 major, 3&4 minor * **D) 3&4 major, 1&2minor** * E) 2&3 major, 1&4 minor ### 9. What is the final, major product of this reaction? * CH3 * OMe * H * OH * Br * 1) H3PO4 * 2) NaN3, * acetone / H2O * (50:50) * a) * OMe * b) * OMe * N3 * c) * OMe * H * d) * OMe * N3 * OMe * A) a) * **B) b)** * C) c) * D) d) ### 10. Which of the following reactions would NOT have a "proton transfer step" in the reaction mechanism: * A * 2-bromo-2-methylbutane + H2O → 2-methyl-2-butanol * SN1 * B * 2-bromobutane + NaOH → (E)-2-butene * E2 * C * T-bromobutane + NaOMe methoxy butane * SN2 * D * 2-bromo-2-methylbutane + tert-butoxide → 2-methyl-1-butene * E2 ### 11. Which of the following reactions will not produce the major product given? * A) * Br * CH3OH * (racemic) * B) * OSO2CF3 * NaBr * acetone * Br * Br * C) * NaBr * acetone * Br * Br * Poor LG * D) * H * CH3 * Br * H * CH3 * CH3CH2ONa * H3C * CH2CH3 * CH2CH3 * A) A * B) B * **C) C** * D) D ### 12. Select the common starting material that can produce these four products as the major product in each of these reaction. * a) * Br * b) * Br ' * c) * Br * d) * Br * e) * Br * A) A * B) B * C) C * **D) D** ### 13. (6 points) For each reaction below state the major reaction pathway that it will undergo (i.e,, SN1 SN2 E1 E2) (OTs is an excellent leaving group) * a) * Br * NaOH * E2 * b) * Br * NaSH * SN2 * c) * Br * H2O * SN1 * d) * OH * H2SO4 * E1 * e) * OTS * H2SO4 * NaBr * SN1/E1 * f) * H * H * NaOH * E2 ### 14. (10 points) Predict the products formed by showing the mechanism of the reaction (using curved arrow notation) of 2-bromo-1,1-dimethylcyclopentane in ethanol. * SN1/E1 ### 15. (16 points) Supply the reactants, reaction conditions or the major product(s) as appropriate to complete the following reactions. Pay attention to stereochemistry wherever pertinent. Make no changes to the given reaction conditions. If no reaction takes under the given condition, clearly indicate it.. * a. CH3 * CH3CHCHCH3 * H2O * acetone * Br * b. CH3 * CH3CHCHCH3 * NaBr * acetone * OH * No RXN * c. CH3CH3 * + Br2 * light * 20 °C * Br * Br * Not included in Exam 3 * d. * + Br2 * RO-OR * 20 °C * Br * Br * Br * CH3 * CH3 ### 16. (6 points) Rank the following compounds in order of increasing Sn2 reaction rate with KI in acetone. * (CH3)3C-Cl * 5 * (CH3)2CH-CH2-CI * 4 * (CH3)2CH-Cl * 3 * CH3CH2CH2CH2-Br * 1 * CH3CH2CH2CH2-Cl * 2 * A < B < C < E < D ### 17. (6 points) Name the following compounds * A. * CH3 * 1-methylbicyclo [4.3.0]nonane * B. * OH * CI * 2 * 3 * (E)-1-chloro-3-methyl-3-penten-2-ol ### 18. (20 points) In the following five reactions, write the type of reaction (SN1, SN2, E1, E2) that will take place in each box. Then write the major product or products formed in each case. * E2 * (CH3)3COK * (CH3)3COH * CI * See * 50% * NaCN * DMF * SN2 * H * H3C * R * H * CH3 * KI * acetone * CH3CH3 * 50% * CH3CH2OH * E2 * CH3CH2ONa * CH3CH2OH * SN1 * H * H * I * I * H * 3 * H