CHEM 346 PROBLEM SET 3 ANSWER KEY 1 Ch 16 49 a H2SO4 SO3H b c d e f g h Cl2 FeCl3 Cl2 FeCl3 O NBS ROOR NO2 Br2 FeBr3 SO3H Cl O Cl H2NNH2 HO Br NaOH OH Cl NH2 NO2 Sn HCl Br CuCN N2 Br CN NaNO2 HCl Br O KMnO4 O OH NaNO2 HCl NH2 N2 Br H2NNH2 HO O OH O HNO3 H2SO4 OH Cu I H2O O OH Br2 FeBr3 KMnO4 HNO3 H2SO4 O2N Cu I H2O Sn HCl H2N O OH Sn HCl O O OH OH NO2 OH Br N2 HO O Cl AlCl3 CH3Cl AlCl3 HNO3 H2SO4 O Cl AlCl3 CH3Cl AlCl3 CH3Cl AlCl3 CH3Cl AlCl3 NaNO2 HCl Ch 16 52 a O O H2SO4 HNO3 O2N O O NO2 O O CH3 1 Mg Et2O 2 D2O CH3 Br D OCH3 1 AlCl3 2 H2O OCH3 O OH O O O OCH3 O OH O N Br2 N Br polybrominated products also possible O N Br OH CH3 1 Br2 h 2 Mg Et2O 3 ethylene oxide 4 H CF3 CF3 FeCl3 Cl2 Ch 16 75 Br H2O acetone Y Cl OH b c d e f Y Y is the intermediate Will be stabilized by electron donating groups at the para position Br Br O Br Br O O Cl HO3S Br Ch 16 76 NO2 F Cl Mechanism NO2 When reacted with OH Nucleophilic aromatic substitution NO2 Product HO NO2 NO2 NO2 X OH X OH HO If X is more electronegative then first step hydroxide attack should be faster If X is weaker base better leaving group then second step should be faster Because fluorine based compound is faster first step must be rate limiting Fluorine is more electronegative than chlorine fluoride is a stronger base than chloride Ch 16 81 O O H NH2 NaNO2 HCl O O O O H N2 O O O O redraw O O H O O H O O NOTE This is drawn incorrectly in the book O O H COO NaCl No reaction 2 Ch 17 11 a H3C OCH3 O O O H3C Cl b c d O H3C OH NaCl NaOH O H3C Cl H3C O Na H3C O CH3 O O NaCl O O H3C O CH3 NaCl No reaction Ch 17 35 O H2SO4 OH H H O O O O O O O O B O O H Ch 17 52 a Reaction should be faster the more electron withdrawing the acyl group is b Collapse of the tetrahedral intermediate should be faster the more electron withdrawing the group is O O O O O O O O Cl Cl O O O O CH3 CH3 3 O A F3C Cl Cl O B O O C NO2 O Ph O E O O D O N H F A B Because CF3 is more electron withdrawing than CH3 B C Acid chlorides are more reactive than esters C D Nitro group makes phenyl ester more electron withdrawing D E Aromatic esters more electron withdrawing than alkyl esters E F Esters are more reactive than amides which is essentially what compound F is analogous to O O O NR2 NR2 NR2 O NR2 4 OAc OTs O O OTs OAc OAc OAc intramolecular fast more reactive fast OAc O O OAc OAc 5 O OTs O O O EtOH B O O H O Et O O OEt 6 Amides are not very reactive due to the capacity of electron donation by the nitrogen lone pair into the carbonyl In amoxicillin the lone pair donation would lead to a strained species which makes it a bad resonance form H N O S N CO2H H N O S N CO2H bad resonance form highly strained Thus this amide is more reactive than a typical amide