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Arom atic like What arethe ? se Arom aticity is an im portant conce include he rocycle pt, s te s (C hapte 25). >300,000 pape since1981! r rs Electrophilic Aromatic Substitution (EAS) Substitution
(Not addition) Me chanism : The Intermediate Cation in EAS The - . . E=H X-ray structureof [C H ] + + 1. Haloge nation: F2 viole C 2, Br2 ne d catalyst ; nt; l e catalyst 1. I2 e ndothe ic rm
Ele ctron poor -HBr 3 Resonancef orm s Re S tops. Br is e -withdrawing, de activate ring s -10 kcal m ol Othe catalytic Le acids: BF3, AlCl3, e r tc. Othe catalytic wis 2. Nitration with nitric acid 2. HNO = HO—NO2
O N+ H N O3 , H 2 SO4 O– Me chanism : C olor: Nu, E, L 3. S ulfonation: Re rsible Re nt is fum sulfuric acid: ve . age ing H2S 4 + S 3 OO
: : O: Val ence : O S O or shel l SO ex panded: O: : O:
: : : SO3 , H 2 SO4 : O S O OH Zwitte rion
S ulfonation : (will be eim com portant in Chapte 16) r Drive by largehe of n at hydration of S 3 hydration O Applications of sulfonic acids: Be ne nze sulfonyl Be chloride chloride Re ROH RC with PC 5 (C call l l hapte 9) r Re O S O N HR O S RN H 2 O Cl O S ROH O O R S ulfonam s ide Re call: Nu: S ulfonic e rs ste S drugs: Antibacte (urinary, m ulfa rial alaria, le...
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This note was uploaded on 09/06/2010 for the course CHEM 10894 taught by Professor Pederson during the Fall '10 term at Berkeley.
- Fall '10