CHEM 220 Winter, 2011 Professor Sasaki EXAM 2 Name . 100 points TOTAL Good Luck! Note: Only answers in the box will be graded. Please check your TA (1). Name Fitz, Brian Whittaker, Aaron Braten, Miles Yan, Yunqi Larsen, Michael Zimmerman, Amanda Viglino, Emilie Section AB,AJ AC,AM AD,AH AE,AK AI, AL AN, AG AA, AF Check Here! If you don't know your section, just write down the time and room name for your quiz section. Chem220 page 2 Name . 1. (24) 2-Methyl-2-propanol (also known as tert-butyl alcohol) undergoes dehydration in the presence of acid (H3O+) to give 2-methylpropene. (a) Write the structures of 2-methyl-2-propanol and 2-methypropene by using the extended structural formula with all the necessary hydrogens. Include the lone-pair electrons, if any, in your structure. 2-methyl-2-propanol 2-methypropene (b) Propose a reasonable reaction mechanism for the above reaction. Use curved arrows to indicate the movement of electrons. Clearly indicate the charges, if any, and their locations. Use the extended structural formula. (c) If 2-methyl-2-butanol, instead of 2-methyl-2-propanol, is treated with acid, what would be the major dehydrationproduct? Write the structure of the product by using the extended structural formula. Chem220 page 3 Name . 2. (25) (a) Draw the structure for the following compounds by using the line-bond formula. You may write methyl groups, if any, in the structure explicitly. (i) 3-methylcyclopentanone (ii) 2-chlorobutanal (iii) meta-bromophenol (b) Supply proper IUPAC names for the following compounds. (i) OH (ii) SH H 3C CH3 C CH2 CH CH3 CH3 (iii) H3C O O CH3 Chem220 page 4 Name 3. (25) (a) Predict the major product(s) in the following reaction. Write the structure of your answer by using the condensed structural formula. Do not use the line-bond formula. (i) H+ OH heat [O] [O] (ii) NH2 excess Br2 acetic acid room temperature 20-min (iii) O HO H3O H (b) Write an example of an organic compound that contains the following functional groups. Use the condensed structural formula for your answer. (i) an ether (ii) a ketal (iii) phenoxide ion . Chem220 page 5 Name . 4. (25) (a) Consider a hemiacetal formed from propanal and methanol. (i) Would the hemiacetal be chiral or achiral? (ii) One of the enatiomers of the hemiacetal is the compound A. O-CH3 C CH3CH2 H OH Compound A Re-draw the structure of the compound A by using the structural template given below. OH C (iii) Draw the Fisher projection of the compound A. O-CH3 CH3 (b) Show how you would carry out the following transformation. You will need to combine more than one reaction to complete. Don't write mechanism. Make sure to supply appropriate reagents for each step. CH3 O CH2