Moorpark College Chemistry 11 Fall Instructor: Professor Gopal. Examination #3: Section Three November 7, 2011.

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1 Moorpark College Chemistry 11 all 2011 Instructor: Professor Gopal Examination #3: Section Three ovember 7, 2011 ame: (print) alkene < alkyne < amine < alcohol < ketone < aldehyde < amide < ester < carboxylic acid Directions: Make sure your examination contains IE total pages (including this cover sheet) when instructed to do so. Answer all the questions in the spaces provided. Be sure to show all your work for partial credit. Question 1. (50 pts.) 2. (15 pts.) 3. (20 pts.) 4. (15 pts.) BUS (9 pts.) TTAL (100 points) Points 1

2 Chemistry 11 all 2011 Examination #3 Answer the following four free response questions. Make sure to show all your work for full credit (100 pts. total). 1. (50 pts. total) Consider the structure of Levofloxacin below, a chemotherapeutic antibiotic used to treat severe or life-threatening bacterial infections. Answer each question related to its structure. C 3 Levofloxacin A. (7 pts.) Label the seven different functional groups in the structure above, studied in this class (although more may be present), found in Levofloxacin. If any alcohols or amines are present, determine if they are primary, secondary, or tertiary. B. (1 pt.) ow many trigonal planar atoms appear in the structure above? C. (1 pt.) ow many trigonal pyramidal atoms appear in the structure above? D. (1 pt.) ow many bent atoms appear in the structure above? E. (1 pt.) ow many diastereomers are possible for Levofloxacin?. (1 pt.) ow many enantiomers are possible for Levofloxacin? G. (1 pts.) Based on your answer to part, does the structure above exhibit an R, S, or neither absolute configuration?. (3 pts.) Does this molecule exhibit cis/trans isomerism? If yes, briefly explain which is present and why? (You should clearly provide structural evidence for your response; merely writing "cis" or "trans" will not earn you any credit). 2

3 C 3 Levofloxacin I. (4 pts.) or the following molecule, determine whether you would expect it to have a IGER or LWER boiling point than Levofloxacin. Briefly explain your answer. Circle one for expected C 3 3 C boiling point compared S P to Levofloxacin: P P IGER or LWER Briefly explain why: J. (8 pts.) In pharmaceutical research, structural analogs of antibiotics are often made in order to see if they have similar biological properties. Below is a structural analog of Levofloxacin called Molecule B. C 3 Molecule B In the boxes below, draw the most stable and least stable chair conformations of Molecule B (you may use an abbreviated notation for extended "R" groups). Least Stable Most Stable 3

4 C 3 Levofloxacin K. (1 pt.) Is Levofloxacin expected to be polar or nonpolar? L. (12 pts. total; 3 pts. each) Based on your accumulated knowledge of organic chemistry to date coupled with the realization that there are multiple functional groups present in Levofloxacin, what is the expected product for each reaction below? Draw the expected product (others may be possible, but you are probably not aware of these additional possibilities to date). 1) Levofloxacin + Cl (include mechanism below) 2) Levofloxacin + 2 in the presence of 2 S 4 (include mechanism below) 4

5 C 3 Levofloxacin 3) Levofloxacin undergoing hydrogenation with a Pd catalyst present 4) Levofloxacin + Br 2 in the presence of CBr 3 M. (1 pt.) Is this molecule aromatic? Write YES or.. (4 pts.) Would you predict that Levofloxacin exhibits better solubility in water or benzene? Briefly explain your response, including references to both the antibiotic and selected solvent. 5

6 . (4 pts.) In 2011, the DA added two Black Box warnings for this drug in reference to spontaneous tendon ruptures and the fact that it may cause worsening of myasthenia gravis symptoms. Such an adverse reaction is a potentially lifethreatening event and may require ventilator support. Would you expect these warnings to be relevant to a racemic mixture of the drug? Briefly explain why or why not. 2. (15 pts. total; 3 pts. each) MECLATURE! Use the appropriate IUPAC notation to name or draw each of the organic structures below: A. B. C. Br 2 (note: - 2 group is called "nitro") D. trans-3,3-diethyl-6-methyl-4-nonene E. 3-methylhexyne 6

7 3. APPLICATIS! (20 pts. total) A. (4 pts.) Assume that you have two unlabeled bottles, one with cyclohexane and one with cyclohexene. ow would you tell them apart by carrying out the learned laboratory techniques in this section? What qualitative experimental results would you expect? B. (4 pts.) Benzene is a liquid at room temperature, but naphthalene (shown below) is a solid. Account for this difference in physical properties using chemical principles learned to date. aphthalene C. (6 pts.) Describe how you could prepare the compound shown below from an alkene: Draw the formula of the alkene (using bond-line notation), name it, and list the inorganic reagents required for this conversion. D. (6 pts.) Consider the ischer projection of D-ribose shown below, an important carbohydrate that will be studied in Sections ive and Six. Applying what you have learned in class, convert the ischer Projection into its proper 3-D bond-line notation using the provided skeletal structure on the right. = C 2 D-ribose 7

8 4. SRT ASWERS! (15 pts. total; 3 pts. each) Briefly define and/or explain each of the terms listed below. A. diastereomer B. Consider the structure of Captopril below. ow many stereocenters (if any) are present? What is the absolute configuration (if applicable) of each stereocenter? What is the primary use of this drug? S C C. structural isomer D. dextrorotatory E. achiral compound 8

9 BUS! (9 pts. max; 3 pts. each) There are numerous different molecules with the molecular formula C 8 8, but there are only 17 constitutional isomers of C 8 8 in which EAC carbon atom is bonded to only E hydrogen atom. Draw (using bond-line notation) 3 different molecules with the formula C 8 8 in which EAC carbon is bonded to E hydrogen atom, and every carbon atom has a full octet. Structure #1 Structure #2 Structure #3 9