Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Chapter 20.SE, Problem 62AP
Interpretation Introduction
Interpretation:
The pKa of five substituted benzoic acids are given. Based on the pKa values, the corresponding substituted benzenes are to be arranged in the increasing order of their reactivity towards
Concept introduction:
Electron releasing substituents present on the benzene ring in substituted benzoic acids destabilize the carboxylate anion and make the acids less acidic. Electron withdrawing substituents present on the benzene ring in substituted benzoic acids stabilize the anion and make the acids more acidic. Lower the pKa value the stronger the acid.
The effects are reversed in aromatic electrophilic substitution reactions. Electron releasing substituents activate the ring towards electrophiles while the electron withdrawing substituents deactivate the ring towards electrophiles.
Thus groups which are good activators reduce the acidity of the acid.
To arrange:
The substituted benzenes in the five
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Chapter 20 Solutions
Organic Chemistry
Ch. 20.1 - Give IUPAC names for the following compounds:Ch. 20.1 - Draw structures corresponding to the following...Ch. 20.2 - Prob. 3PCh. 20.2 - The Ka for dichloroacetic acid is 3.32 Ă— 10-2....Ch. 20.3 - Calculate the percentages of dissociated and...Ch. 20.4 - Which would you expect to be a stronger acid, the...Ch. 20.4 - Dicarboxylic acids have two dissociation...Ch. 20.4 - The pKa of p-cyclopropylbenzoic acid is 4.45. Is...Ch. 20.4 - Prob. 9PCh. 20.5 - Prob. 10P
Ch. 20.6 - Prob. 11PCh. 20.6 - How might you carry out the following...Ch. 20.7 - Prob. 13PCh. 20.7 - Prob. 14PCh. 20.8 - Cyclopentanecarboxylic acid and...Ch. 20.8 - Prob. 16PCh. 20.SE - Prob. 17VCCh. 20.SE - Prob. 18VCCh. 20.SE - The following carboxylic acid can’t be prepared...Ch. 20.SE - Electrostatic potential maps of anisole and...Ch. 20.SE - Predict the product(s) and provide the mechanism...Ch. 20.SE - Predict the product(s) and provide the mechanism...Ch. 20.SE - Prob. 23MPCh. 20.SE - Predict the product(s) and provide the complete...Ch. 20.SE - Acid-catalyzed hydrolysis of a nitrile to give a...Ch. 20.SE - Prob. 26MPCh. 20.SE - Naturally occurring compounds called cyanogenic...Ch. 20.SE - 2-Bromo-6, 6-dimethylcyclohexanone gives 2,...Ch. 20.SE - Naturally occurring compounds called terpenoids,...Ch. 20.SE - In the Ritter reaction, an alkene reacts with a...Ch. 20.SE - Give IUPAC names for the following compounds:Ch. 20.SE - Prob. 32APCh. 20.SE - Prob. 33APCh. 20.SE - Prob. 34APCh. 20.SE - Prob. 35APCh. 20.SE - Prob. 36APCh. 20.SE - Prob. 37APCh. 20.SE - Prob. 38APCh. 20.SE - Calculate the Ka's for the following acids: (a)...Ch. 20.SE - Thioglycolic acid, HSCH2CO2H, a substance used in...Ch. 20.SE - Prob. 41APCh. 20.SE - Prob. 42APCh. 20.SE - How could you convert butanoic acid into the...Ch. 20.SE - How could you convert each of the following...Ch. 20.SE - How could you convert butanenitrile into the...Ch. 20.SE - How would you prepare the following compounds from...Ch. 20.SE - Prob. 47APCh. 20.SE - Using 13CO2 as your only source of labeled carbon,...Ch. 20.SE - Prob. 49APCh. 20.SE - Which method-Grignard carboxylation or nitrile...Ch. 20.SE - Prob. 51APCh. 20.SE - Prob. 52APCh. 20.SE - Propose a structure for a compound C6H12O2 that...Ch. 20.SE - Prob. 54APCh. 20.SE - How would you use NMR (either 13C or 1H) to...Ch. 20.SE - Prob. 56APCh. 20.SE - A chemist in need of 2,2-dimethylpentanoic acid...Ch. 20.SE - Prob. 58APCh. 20.SE - Prob. 59APCh. 20.SE - Prob. 60APCh. 20.SE - Prob. 61APCh. 20.SE - Prob. 62APCh. 20.SE - Prob. 63APCh. 20.SE - The following pKa values have been measured....Ch. 20.SE - Identify the missing reagents a-f in the following...Ch. 20.SE - Propose a structure for a compound, C4H7N, that...Ch. 20.SE - Prob. 67APCh. 20.SE - The 1H and 13C NMR spectra below belong to a...Ch. 20.SE - Propose structures for carboxylic acids that show...Ch. 20.SE - Carboxylic acids having a second carbonyl group...
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