Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Chapter 17.SE, Problem 64AP
Interpretation Introduction
Interpretation:
p-Nitrophenol and 2,6-dimethyl-4-nitrophenol both have a pKa of 7.15 but 3,5-dimethyl-4-nitrophenol has pKa of 8.25. Why 3,5-dimethyl-4-nitrophenol is much less acidic is to be explained.
Concept introduction:
Resonance delocalization occurs only when the molecule is planar facilitating the overlapping of the orbitals. If the substituent groups present prevent co-planarity of the molecule then resonance is not possible.
pKa = -log Ka, where Ka is the dissociation constant of the acid. Thus a stronger acid has a low pKa value.
To explain:
Why 3,5-dimethyl-4-nitrophenol is much less acidic with pKa of 8.25 when compared to p-nitrophenol and 2,6-dimethyl-4-nitrophenol both of which have a pKa of 7.15.
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Chapter 17 Solutions
Organic Chemistry
Ch. 17.1 - Give IUPAC names for the following compounds:Ch. 17.1 - Prob. 2PCh. 17.2 - The following data for isomeric four-carbon...Ch. 17.2 - Rank the following substances in order of...Ch. 17.2 - Prob. 5PCh. 17.3 - Prob. 6PCh. 17.4 - What reagent would you use to accomplish each of...Ch. 17.4 - Prob. 8PCh. 17.5 - Prob. 9PCh. 17.5 - Prob. 10P
Ch. 17.5 - Use the reaction of a Grignard reagent with a...Ch. 17.6 - How would you carry out the following...Ch. 17.6 - What products(s) would you expect from dehydration...Ch. 17.7 - What alcohols would give the following products on...Ch. 17.7 - What products would you expect from oxidation of...Ch. 17.8 - TMS ethers can be removed by treatment with...Ch. 17.9 - Show the mechanism for the reaction of...Ch. 17.11 - Prob. 18PCh. 17.11 - When the 1HNMR spectrum of an alcohol is run in...Ch. 17.SE - Give IUPAC names for the following compounds:Ch. 17.SE - Draw the structure of the carbonyl compound(s)...Ch. 17.SE - Prob. 22VCCh. 17.SE - Prob. 23VCCh. 17.SE - Name and assign R or S stereochemistry to the...Ch. 17.SE - Evidence for the intermediate carbocations in the...Ch. 17.SE - Acid-catalyzed dehydration of 2,...Ch. 17.SE - Prob. 27MPCh. 17.SE - Treatment of the following epoxide with aqueous...Ch. 17.SE - Prob. 29MPCh. 17.SE - Prob. 30MPCh. 17.SE - Identify the type of substitution mechanism (SN1,...Ch. 17.SE - The conversion of 3 alcohols into alkenes under...Ch. 17.SE - Prob. 33MPCh. 17.SE - The trimethylsilyl (TMS) protecting group is one...Ch. 17.SE - When the alcohol below is treated with POCI3 and...Ch. 17.SE - Phenols generally have lower pKa’s than...Ch. 17.SE - Give IUPAC names for the following compounds:Ch. 17.SE - Draw and name the eight isomeric alcohols with...Ch. 17.SE - Prob. 39APCh. 17.SE - Named bombykol, the sex pheromone secreted by the...Ch. 17.SE - Carvacrol is a naturally occurring substance...Ch. 17.SE - What Grignard reagent and what carbonyl compound...Ch. 17.SE - What carbonyl compounds would you reduce to...Ch. 17.SE - What carbonyl compounds might you start with to...Ch. 17.SE - Prob. 45APCh. 17.SE - What products would you obtain from reaction of...Ch. 17.SE - Prob. 47APCh. 17.SE - How would you prepare the following compounds from...Ch. 17.SE - Prob. 49APCh. 17.SE - What products would you expect to obtain from...Ch. 17.SE - Prob. 51APCh. 17.SE - Propose structures for alcohols that have the...Ch. 17.SE - Propose a structure consistent with the following...Ch. 17.SE - The 1HNMR spectrum shown is that of...Ch. 17.SE - A compound of unknown structure gave the following...Ch. 17.SE - Propose a structure for a compound C15H24O that...Ch. 17.SE - Prob. 57APCh. 17.SE - Prob. 58APCh. 17.SE - Rank the following substituted phenols in order of...Ch. 17.SE - Benzvl chloride can be converted into benzaldehvde...Ch. 17.SE - Prob. 61APCh. 17.SE - Prob. 62APCh. 17.SE - Prob. 63APCh. 17.SE - Prob. 64APCh. 17.SE - Prob. 65APCh. 17.SE - Prob. 66APCh. 17.SE - Dehydration of trans-2-methylcyclopentanol with...Ch. 17.SE - 2, 3-Dimethyl-2, 3-butanediol has the common name...Ch. 17.SE - As a rule, axial alcohols oxidize somewhat faster...Ch. 17.SE - Prob. 70APCh. 17.SE - A problem often encountered in the oxidation of...Ch. 17.SE - Identify the reagents a-f in the Following scheme:Ch. 17.SE - Prob. 73APCh. 17.SE - Prob. 74APCh. 17.SE - Compound A, C8H10O, has the IR and 1H NMR spectra...Ch. 17.SE - Prob. 76APCh. 17.SE - Prob. 77AP
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