APPENDIX 2 114 11.5CH CH3 ON 11.7(CH3)3C 11.8(b)C,HsCH,OC(CH3)3 (c) Chs=n:(d)ChS CH?SH 11.9 1, 2-Dihydronaphthalene, 101 k/mol (24.1 kcal/mol): 1, 4-dihydronaphthalene, 113 k/mol 11.10(b)C6HsCHCH,OH (c)C6HsCHCH2 Br (d)C6HSCH--CH2+ C,,H CH3 11.11 Styrene, 4393 kJ/mol (1050 kcal/mol); cyclooctatetraene, 4543 kJ/mol (1086 kcal/mol) 11.12 Diels-Alder reaction 11.13(b) Five doubly occupied bonding orbitals plus two half-filled nonbonding orbitals plus five 11.14 Divide the heats of combustion by the number of carbons. The two aromatic hydrocarbons benzene and [18]-annulene) have heats of combustion per carbon that are less than those of the nonaromatic hydrocarbons(cyclooctatetraene and [161-annulene) On a per carbon basis, the aromatic hydrocarbons have lower potential energy(are more stable) than the nonaromatic hydrocarbons H Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
A-26 APPENDIX 2 11.4 11.5 11.6 (b) 11.7 11.8 (b) C6H5CH2OC(CH3)3 (c) (d) C6H5CH2SH (e) C6H5CH2I 11.9 1,2-Dihydronaphthalene, 101 kJ/mol (24.1 kcal/mol); 1,4-dihydronaphthalene, 113 kJ/mol (27.1 kcal/mol) 11.10 (b) (c) (d) 11.11 Styrene, 4393 kJ/mol (1050 kcal/mol); cyclooctatetraene, 4543 kJ/mol (1086 kcal/mol) 11.12 Diels–Alder reaction 11.13 (b) Five doubly occupied bonding orbitals plus two half-filled nonbonding orbitals plus five vacant antibonding orbitals 11.14 Divide the heats of combustion by the number of carbons. The two aromatic hydrocarbons (benzene and [18]-annulene) have heats of combustion per carbon that are less than those of the nonaromatic hydrocarbons (cyclooctatetraene and [16]-annulene). On a per carbon basis, the aromatic hydrocarbons have lower potential energy (are more stable) than the nonaromatic hydrocarbons. 11.15 C6H5CH CH2 O C6H5CHCH2Br C6H5CO2H OH C6H5CHCH2OH CH3 C6H5CH2N N N CO2H CO2H (CH3)3C OCH3 O2N BrCH2 CH3 CH3 H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H
APPENDIX 2 A-2 H 11.1 + NH- H NH3 11.18(b)Cyclononatetraenide anion is aromatic 11.19 Indole is more stable than isoindole Six-membered Six-membered bonds as benzene Isoindole less stable Benzoxazole Benzothiazo 11.21 CHAPTER 12 12.1 The positive charge is shared by the three carbons indicated in the three most stable reso- H H < ovided that these structures contribute equally, the resonance picture coincides with the Mo treat- nt in assigning one third of a positive charge (+ 0.33)to each of the indicated carbons. Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
APPENDIX 2 A-27 11.16 11.17 11.18 (b) Cyclononatetraenide anion is aromatic. 11.19 Indole is more stable than isoindole. 11.20 11.21 CHAPTER 12 12.1 The positive charge is shared by the three carbons indicated in the three most stable resonance structures: Provided that these structures contribute equally, the resonance picture coincides with the MO treatment in assigning one third of a positive charge ( 0.33) to each of the indicated carbons. H H H H H H H H H H H H H H H H H H H H H H3O N N H N H N H N O Benzoxazole N S Benzothiazole N H Indole: more stable Isoindole: less stable NH Six-membered ring corresponds to benzene. Six-membered ring does not have same pattern of bonds as benzene. NH3 NH2 H H H H H H H H H H H H H H H H H H H H H H H H H H H H
APPENDIX 2 122 SO3H HaC 123 12. 4 The major product is isopropylbenzene lonization of 1-chloropropane is accompanied by a hydride shift to give CH3 CHCH3, which then attacks benzene +H-0SO,OH一 +OSO,OH H HSOa 12.7 CHO 一CCH2CH(CH3)2 OCH3 128 CCH,,COH Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
A-28 APPENDIX 2 12.2 12.3 12.4 The major product is isopropylbenzene. Ionization of 1-chloropropane is accompanied by a hydride shift to give , which then attacks benzene. 12.5 12.6 12.7 12.8 O CCH2CH2COH O OCH3 OCH3 CH3O O CCH2CH(CH3)2 H2SO4 benzoyl peroxide, heat NBS NaOCH2CH3 heat Br H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H OSO2OH OSO2OH CH3CHCH3 CH3 H3C CH3 H3C SO3H NO2 CH3 CH3
APPENDIX 2 12.9(b) Friedel-Crafts acylation of benzene with(CH3) CCCl, followed by reduction with Zn(Hg) and hydrochloric acid 12. 10(b) Toluene is 1.7 times more reactive than tert-butylbenzene(c) Ortho(10%), meta(6.7%), para(83.3%) 12.11 -CHCl CHCl ing ortho, para-directing 1212(b) NH? NH NH2 1214(b) COCH CCH2CH ON O2N 12.15 The group -N(CH3)3 is strongly deactivating and meta-directing. Its positively trogen makes it a powerful electron-withdrawing substituent. It resembles a nitro group NO2 2.17(b) (d)CHC- OCH3 O, N OCH3 (f) NO, Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
APPENDIX 2 A-29 12.9 (b) Friedel–Crafts acylation of benzene with , followed by reduction with Zn(Hg) and hydrochloric acid 12.10 (b) Toluene is 1.7 times more reactive than tert-butylbenzene. (c) Ortho (10%), meta (6.7%), para (83.3%) 12.11 12.12 (b) (c) 12.13 12.14 (b) (c) 12.15 The group ± N(CH3)3 is strongly deactivating and meta-directing. Its positively charged nitrogen makes it a powerful electron-withdrawing substituent. It resembles a nitro group. 12.16 12.17 (b) (c) (d) (e) (f) OCH3 Br Br NO2 OCH3 NO2 CH3 OCH3 NO2 CH3C O NO2 O2N NO2 NO2 Cl Cl CH2 Cl Cl and Cl CH2 Cl O2N CCH2CH3 O O2N COCH3 O and O2N NO2 NH2 H Br NH2 H Br NH2 H Br NH2 H Br NH2 Br H NH2 Br H NH2 Br H CH2Cl Deactivating ortho, para-directing CHCl2 Deactivating ortho, para-directing CCl3 Deactivating meta-directing (CH3)3CCCl O
A-30 APPENDIX 2 12.18 m-Bromonitrobenzene ①=① p-Bromonitrobenzene Br NO COH CO,H Na Cr-O- 12.19 H SO,H Formed faster The hydrogen at C-8( the one shown in the structural formulas) crowds the -SO3h group in th less stable isomer 12.21 CHAPTER 13 13.1141T 13.225.2MHz 13.3(a)6.88 ppm;(b) higher field; more shielded then H in CH, CCla appears 4.6 ppm upfield of 7.28 ppm. Its chemical shift is b2/ppm ppm, 13.5 The chemical shift of the methyl protons is 8 2.2 ppm. The chemical shift of the protons 13.6(b) Five:(c) two: (d)two:(e)three: (f one: (g) four;(h) three 13.7(b)One:(c)one;(d)one:(e) four;(f) four 13.8(b)One signal (singlet); (c) two signals(doublet and triplet);(d) two signals(both singlets); (e) two signals( doublet and quartet) 13. 9 (b) Three signals (singlet, triplet, and quartet);(c)two signals(triplet and quartet);(d) three ignals(singlet, triplet, and quartet);(e) four signals (three triplets and quartet) Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
A-30 APPENDIX 2 12.18 m-Bromonitrobenzene: p-Bromonitrobenzene: 12.19 12.20 The hydrogen at C-8 (the one shown in the structural formulas) crowds the ±SO3H group in the less stable isomer. 12.21 CHAPTER 13 13.1 1.41 T 13.2 25.2 MHz 13.3 (a) 6.88 ppm; (b) higher field; more shielded 13.4 H in CH3CCl3 is more shielded than H in CHCl3. If H in CHCl3 appears at 7.28 ppm, then H in CH3CCl3 appears 4.6 ppm upfield of 7.28 ppm. Its chemical shift is 2.7 ppm. 13.5 The chemical shift of the methyl protons is 2.2 ppm. The chemical shift of the protons attached to the aromatic ring is 7.0 ppm. 13.6 (b) Five; (c) two; (d) two; (e) three; (f) one; (g) four; (h) three 13.7 (b) One; (c) one; (d) one; (e) four; (f) four 13.8 (b) One signal (singlet); (c) two signals (doublet and triplet); (d) two signals (both singlets); (e) two signals (doublet and quartet) 13.9 (b) Three signals (singlet, triplet, and quartet); (c) two signals (triplet and quartet); (d) three signals (singlet, triplet, and quartet); (e) four signals (three triplets and quartet) SO3H S Formed faster H SO3H More stable H SO3H CO2H NO2 CH3 CO2H Na2Cr2O7 H2SO4, H2O, heat HNO3 H2SO4 Br Br NO2 Br NO2 HNO3 H2SO4 Br2 FeBr3 NO2 Br NO2 HNO3 H2SO4 Br2 FeBr3