Organic Chem Exam II: Aromaticity, Reactions, & Mechanisms, Exams of Organic Chemistry

Download Organic Chem Exam II: Aromaticity, Reactions, & Mechanisms and more Exams Organic Chemistry in PDF only on Docsity! Name_______________________________ Chem 2314 Organic Chemistry Lecture Seton Hall University Instructor: Prof. John R. Sowa, Jr. March19, 2007 Exam II 100 points Q1________ Q2________ Q3________ Q4________ Q5________ Total_______ Good Luck! 1) (18 points) Aromaticity a) (6 pts) Compare the stability of aromatic compounds relative to non-aromatic compounds and antiaromatic compounds. In addition, list the four major descriptors of an aromatic compound. b) (6 pts) Use the 4n or 4n+2 rule to characterize the following compounds as aromatic or antiaromatic (show your calculation). i) ii) iii) N iv) v) vi)O c) (6 pts) Cyclooctatetraene is a known compound, stable at room temperature. Draw the MO diagram of cyclooctatetrane using the polygon rule. Label the bonding, non-bonding and and antibonding levels, Describe in words why a planar structure for this compound would not be favored. 4) (20 Points) Reaction mechanisms. a) (10 pts) Write the mechanism for the following transformation. Show in your mechanism why the para product is favored. HNO3, H2SO4 (= NO2+) NO2 b) (10 pts) Write the mechanism for the following reaction. Show all important intermediates. H O OH O OH TsOH (cat) 5) (21 points) Schiff base reaction. a) (12 pts) Write the mechanism for the following Schiff base reaction. O NH2CH3 pH ~ 5 N CH3 b) (9 pts, 3 ea) Supply the missing reagent. O pH ~ 5 N OH O pH ~ 5 N O pH ~ 5 N NH2 + + + NO2 O2N