Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Question
Chapter 18.SE, Problem 68GP
Interpretation Introduction
Interpretation:
Given that the treatment of α-bromoacetophenone, obtained from acetophenone by bromination, with NaBH4 yields an
Concept introduction:
The nucleophilic attack attack of the hydride ion on the carbonyl carbon of the bromoketone and the following internal nucleophilic attack by the negatively charged oxide ion and to eliminate a bromide ion will lead to the formation of the epoxide.
To give:
Given that the treatment of α-bromoacetophenone, prepared from acetophenone, with NaBH4 yields an epoxide. The structure of the epoxide is to be shown and its formation is to be explained.
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Propose a mechanism for this example of a pinacol rearrangemen
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Ketone reacted with
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2) (i) DIBAL-H (ii). H3O+
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TABLE OF REAGENTS
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CHO
MacBook Air
9) C6H5 CH2 P(C6H5)3; NaOH
10) PCC (an oxidant)
11) NaCN, H₂SO4
12) PhCH2CHO, H3O*
H₂C
ཏཱཏི 1 ནི
OH
1. Br2, PBг3
2. H₂O
H3C
OH
Br
The a-bromination of carbonyl compounds by Br2 in acetic acid is limited to aldehydes and ketones because acids, esters, and amides don't enolize to a sufficient extent. Carboxylic acids, however, can
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Draw curved arrows to show the movement of electrons in this step of the mechanism.
Arrow-pushing Instructions
:0:
H3C
Br
Br
+
:::OH2
Br
H₂O
H3C
Br
за
Chapter 18 Solutions
Organic Chemistry
Ch. 18.1 - Name the following ethers:Ch. 18.2 - Why do you suppose only symmetrical ethers are...Ch. 18.2 - How would you prepare the following ethers using a...Ch. 18.2 - Review the mechanism of oxymercuration shown in...Ch. 18.2 - How would you prepare the following ethers? Use...Ch. 18.2 - Prob. 6PCh. 18.3 - Prob. 7PCh. 18.3 - Write the mechanism of the acid-induced cleavage...Ch. 18.3 - Why are HI and HBr more effective than HCl in...Ch. 18.4 - What product would you expect from Claisen...
Ch. 18.5 - Prob. 11PCh. 18.6 - Predict the major product of each of the following...Ch. 18.6 - Prob. 13PCh. 18.6 - Predict the major product of the following...Ch. 18.7 - 15-Crown-5 and 12-crown-4 ethers complex Na+ and...Ch. 18.8 - Prob. 16PCh. 18.8 - 2-Butene-l-thiol is one component of skunk spray....Ch. 18.9 - The 1H NMR spectrum shown is that of a cyclic...Ch. 18.SE - Give IUPAC names for the following compounds...Ch. 18.SE - Show the product, including stereochemistry, that...Ch. 18.SE - Prob. 21VCCh. 18.SE - Treatment of the following alkene with a...Ch. 18.SE - Prob. 23MPCh. 18.SE - Prob. 24MPCh. 18.SE - Predict the product(s) and provide the mechanism...Ch. 18.SE - The alkoxymercuration of alkenes involves the...Ch. 18.SE - Predict the product(s) and provide the mechanism...Ch. 18.SE - Predict the product(s) and provide the mechanism...Ch. 18.SE - Prob. 29MPCh. 18.SE - Ethers undergo an acid-catalyzed cleavage reaction...Ch. 18.SE - Treatment of 1, 1-diphenyl-l, 2-epoxyethane with...Ch. 18.SE - Fluoxetine, a heavily prescribed antidepressant...Ch. 18.SE - When 2-methyl-2, 5-pentanediol is treated with...Ch. 18.SE - Prob. 34MPCh. 18.SE - Prob. 35MPCh. 18.SE - Aldehydes and ketones undergo acid-catalyzed...Ch. 18.SE - Propose a mechanism to account for the following...Ch. 18.SE - Prob. 38APCh. 18.SE - Prob. 39APCh. 18.SE - How would you prepare the following ethers?Ch. 18.SE - Prob. 41APCh. 18.SE - tert-Butyl ethers can be prepared by the reaction...Ch. 18.SE - Treatment of trans-2-chlorocyclohexanol with NaOH...Ch. 18.SE - Predict the products of the following ether...Ch. 18.SE - Prob. 45APCh. 18.SE - Prob. 46APCh. 18.SE - Write the mechanism of the hydrolysis of cis-5,...Ch. 18.SE - Prob. 48APCh. 18.SE - Acid-catalyzed hydrolysis of a 1,...Ch. 18.SE - Prob. 50APCh. 18.SE - Epoxides are reduced by treatment with lithium...Ch. 18.SE - Prob. 52APCh. 18.SE - The red fox (Vulpes vulpes) uses a chemical...Ch. 18.SE - Anethole, C10H12O, a major constituent of the oil...Ch. 18.SE - Propose structures for compounds that have the...Ch. 18.SE - Prob. 56GPCh. 18.SE - How would you synthesize anethole (Problem 18-54)...Ch. 18.SE - How could you prepare benzyl phenyl ether from...Ch. 18.SE - Meerwein's reagent, triethyloxonium...Ch. 18.SE - Prob. 60GPCh. 18.SE - Prob. 61GPCh. 18.SE - The Zeisel method is an old analytical procedure...Ch. 18.SE - Prob. 63GPCh. 18.SE - Prob. 64GPCh. 18.SE - Prob. 65GPCh. 18.SE - Identify the reagents a-e in the following scheme:Ch. 18.SE - Propose structures for compounds that have the...Ch. 18.SE - Prob. 68GPCh. 18.SE - Prob. 69GPCh. 18.SE - Predict the product(s) if the starting materials...
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