11 11 2024 13 14 Chapter 11 carey Chapter 11 Arenes and Aromaticity Chapter 11 Arenes and Aromaticity 1 What is the IUPAC name of the following compound ortho ethyliodobenzene para ethyliodobenzene para ethylphenyl iodide 1 ethyl 4 iodo 1 3 5 cyclohexatriene 2 How many isomeric dichlorobenzenes are there A no isomers only a single compound B 2 C 3 D 4 Ans C 3 What is the IUPAC name of the following compound 4 tert butyl 3 chlorophenol ortho tert butylchlorophenol 4 tert butyl 5 chlorophenol 2 tert butyl meta chlorophenol A B Ans C A B Ans A C D C D Page 153 about blank 1 17 11 11 2024 13 14 Chapter 11 carey Chapter 11 Arenes and Aromaticity 4 What is the IUPAC name of the following compound A B 6 phenylheptane 2 benzylheptane Ans D C D 2 heptylbenzene 2 phenylheptane 5 Which of the following is 2 chloro 4 ethylphenol A A B B C C D D Ans A 6 What is the correct IUPAC name of the following compound A 1 4 dibromo 3 nitrobenzene C 2 nitro 1 4 dibromobenzene Page 154 about blank 2 17 11 11 2024 13 14 Chapter 11 carey Ans B B C D Ans B A B Ans C Chapter 11 Arenes and Aromaticity B 1 4 dibromo 2 nitrobenzene D 1 nitro 2 5 dibromobenzene 7 How many isomeric tribromobenzenes are possible A one B two C three D four Ans C 8 Which of the following is not true concerning the structure of benzene A All C C C bond angles are exactly 120 o The carbon carbon bonds rapidly alternate between single and double bonds The six hydrogens are equivalent The bonds are completely conjugated 9 What is the IUPAC name of the following compound 4 6 dichloro 2 benzoic acid 3 5 dichlorobenzoic acid 2 4 dichlorobenzoic acid meta dichlorobenzoic acid C D 10 The total number of resonance forms of the cyclopentadienide anion C is 5H5 A two B three C four D five Ans D 11 Which of the following ions are aromatic species A I and III B II and III C II and IV D III and IV Ans B Page 155 about blank 3 17 11 11 2024 13 14 Chapter 11 carey Chapter 11 Arenes and Aromaticity 12 Identify the aromatic compounds A I and II B III and IV C I II and IV D all of them Ans C 13 How many isomeric bromoanthracenes are there A none only one structure B two C three D four Ans C 14 Which of the following reacts at the fastest rate when heated with N bromosuccinimide NBS and benzoyl peroxide in carbon tetrachloride at 80oC A toluene C isopropylbenzene cumene B ethylbenzene D tert butylbenzene 15 The Birch reduction of benzene with sodium in NH 3 CH3 OH goes by a four step Ans C B C D Ans B mechanism The first step is the A transfer of a proton from CH OH to benzene 3 transfer of an electron from Na to benzene transfer of an electron from benzene to NH 3 transfer of a hydride ion H from NH to benzene 3 Page 156 about blank 4 17 11 11 2024 13 14 Chapter 11 carey Chapter 11 Arenes and Aromaticity 16 Which species is oxidized in the Birch reduction shown below A benzene B Na C CH OH D NH Ans B 3 3 17 The benzyl carbocation is shown below Besides the benzylic carbon identify any other carbon atoms which carry a partial positive charge based on resonance theory Ans A Ans D A B C D A ortho and para carbon atoms C meta and para carbon atoms B meta carbon atoms D ortho and meta carbon atoms 18 Side chain oxidations of alkylbenzenes with Na 2Cr2O7 and H 2SO H4 2 O will not work if the alkyl side chain has A only one carbon B four or more carbons no benzylic hydrogens benzylic hydrogens C D 19 Which of the following are consistent with the requirements for aromaticity electrons in a ring I A system with delocalized II 4n electrons in the ring III All the ring atoms must be carbons IV 4n 2 A I and II B I and IV C I II and III D I III and IV Ans B electrons in the ring 20 Cyclopentadiene is unusually acidic for a hydrocarbon Why Cyclopentadiene is aromatic The conjugate base of cyclopentadiene is aromatic Cyclopentadiene is an unstable diradical The conjugate base of cyclopentadiene is an unstable diradical Page 157 about blank 5 17 11 11 2024 13 14 Chapter 11 carey Chapter 11 Arenes and Aromaticity Ans B form a carbanion 21 Which of the following would most readily react with a strong base such as NaNH to 2 A A B B C C D D Ans A 22 What is the value of from Huckel s rule for the following aromatic compound n 3 B n 4 C n 8 D n 9 n A Ans B 23 The name of the following compound is A meta bromoanisole C meta bromoaniline B meta bromonitrobenzene D meta bromophenol Ans C Page 158 about blank 6 17 11 11 2024 13 14 Chapter 11 carey Chapter 11 Arenes and Aromaticity 24 Which hydrogen atom would be most easily extracted by a bromine atom A 1 B 2 C 3 D 4 Ans A 25 What is the product of the reaction shown below A I B II C III D IV Ans D Page 159 about blank 7 17 11 11 2024 13 14 Chapter 11 carey Chapter 11 Arenes and Aromaticity 26 Propylbenzene is subjected to the sequence of reactions below What is the final product A A B B C C D D Ans B 27 A compound X C 8H10 is oxidized to benzoic acid with potassium dichromate K 2Cr O2 7 in sulfuric acid What is compound X A para Ans D xylene B propylbenzene C styrene D ethylbenzene 28 Acid catalyzed dehydration of cis 2 phenylcyclopentanol gives 1 phenylcyclopentene 4 phenylcyclopentene phenylcyclopentane 1 phenylcyclopentanol C D A B Ans A Page 160 about blank 8 17 11 11 2024 13 14 Chapter 11 carey Chapter 11 Arenes and Aromaticity 29 Predict the major organic product in the following reaction A A B B C C D D Ans B 30 Which of the following has the fastest rate of S 1 hydrolysis in aqueous acetone N 31 Select the best method to convert styrene C 6H CH CH 5 to 2 phenylethanol with 2 A I B II C III D IV Ans C minimal by product formation A H2O H2SO4 1 BH THF 2 H NaOH 2O2 3 1 HBr 2 KOH H O2 1 HBr peroxides 2 NaOH H O2 B C D Ans B 32 Which of the following would be a correct number of electrons for a planar monocyclic completely conjugated polyene to be aromatic A 3 B 8 C 18 D 24 Ans C Page 161 about blank 9 17 11 …