Organic Chemistry Plus Masteringchemistry With Pearson Etext, Global Edition
9th Edition
ISBN: 9781292151229
Author: Wade, LeRoy G.
Publisher: PEARSON
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Textbook Question
Chapter 18, Problem 18.41SP
Acetals can serve as protecting groups for 1,2-
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Br2, H3O+
གོ་ཤི་ན་ཤི་
H3C CH3
CH3
CH3
Aldehydes and ketones can be halogenated at their a-position by reaction with Cl₂, Br2, or 12, under acidic conditions. Using Br2 under acidic conditions, an intermediate enol is formed which adds
bromine at the a-position. The reaction stops after the addition of one bromine because the electron-withdrawing halogen decreases the basicity of the carbonyl oxygen, making the protonation less
favorable.
Draw curved arrows to show the movement of electrons in this step of the mechanism.
Arrow-pushing Instructions
:OH
:OH
Br-Br
H3C
H3C.
Br
Br
CH₂
H₂
H3C CH3
H3C CH3
2b
CH3
གོན་ནི། ཡོན་
Br₂,
H₂C
CH₂Br
H3C CH3
H₂C CH3
Aldehydes and ketones can be halogenated at their a-position by reaction with Cl₂, Br2, or 12, under acidic conditions. Using Br₂ under acidic conditions, an intermediate enol is formed which adds
bromine at the a-position. The reaction stops after the addition of one bromine because the electron-withdrawing halogen decreases the basicity of the carbonyl oxygen, making the protonation less
favorable.
Draw curved arrows to show the movement of electrons in this step of the mechanism.
Arrow-pushing Instructions
:0:
:OH
н-он
H-OH₂
H₂O
H₂C.
H3C.
CH3
CH3
H3C CH3
H3C CH3
Σα
Which sequence of steps will give the highest yield of a carboxylic ester product?
Mix 0.1 mole of benzoic acid (C6H5CO2H) with 1.0 mol SOC12, remove unreacted SOC12, then add 0.1 mole of isopropyl alcohol
O Mix 0.1 mole of benzoic acid (C6H5CO2H) with 0.1 mol of NaOH, then add 1.0 mol of isopropyl alcohol and heat, Men remove any unreacted isopropyl alcohol
O Mix 0.1 mole of benzoic acid (C6H5CO2H) with 0.1 mol of NaOH, then add 0.1 mol of isopropyl alcohol and heat
Mix 0.1 mole of methyl benzoate (C6H5-(C=0)-OCH3) with 0.1 mol of isopropyl alcohol and stir overnight
Chapter 18 Solutions
Organic Chemistry Plus Masteringchemistry With Pearson Etext, Global Edition
Ch. 18.3 - Give the IUPAC name and (if possible) a common...Ch. 18.5D - NMR spectra for two compounds are given here,...Ch. 18.5D - Why were no products from the McLafferty...Ch. 18.5D - Use equations to show the fragmentation leading to...Ch. 18.5E - Prob. 18.5PCh. 18.7D - Show how you would synthesize each compound from...Ch. 18.8 - Prob. 18.7PCh. 18.9 - Predict the products of the following reactions....Ch. 18.9 - Show how the following transformations may be...Ch. 18.10 - Prob. 18.10P
Ch. 18.11 - Show how you would accomplish the following...Ch. 18.11 - Prob. 18.12PCh. 18.12 - Propose mechanisms for a. the acid-catalyzed...Ch. 18.12 - Rank the following compounds in order of...Ch. 18.13 - Prob. 18.15PCh. 18.13 - Show how you would accomplish the following...Ch. 18.14 - Prob. 18.17PCh. 18.14 - Prob. 18.18PCh. 18.14 - Prob. 18.19PCh. 18.14 - Prob. 18.20PCh. 18.15 - 2,4-Dinitrophenylhydrazine is frequently used for...Ch. 18.15 - Prob. 18.22PCh. 18.15 - Prob. 18.23PCh. 18.16 - Prob. 18.24PCh. 18.16 - Prob. 18.25PCh. 18.16 - Show what alcohols and carbonyl compounds give the...Ch. 18.16 - In the mechanism for acetal hydrolysis shown, the...Ch. 18.16 - Prob. 18.28PCh. 18.17 - Show how you would accomplish the following...Ch. 18.18 - Prob. 18.30PCh. 18.18 - Prob. 18.31PCh. 18.18 - Prob. 18.32PCh. 18.18 - Show how Wittig reactions might be used to...Ch. 18.19 - Predict the major products of the following...Ch. 18.20C - Prob. 18.35PCh. 18.20C - Predict the major products of the following...Ch. 18 - Draw structures of the following derivatives. a....Ch. 18 - Prob. 18.38SPCh. 18 - Predict the major products of the following...Ch. 18 - Rank the following carbonyl compounds in order of...Ch. 18 - Acetals can serve as protecting groups for...Ch. 18 - Sketch the expected proton NMR spectrum of...Ch. 18 - A compound of formula C6H10O2 shows only two...Ch. 18 - The proton NMR spectrum of a compound of formula...Ch. 18 - The following compounds undergo McLafferty...Ch. 18 - An unknown compound gives a molecular ion of m/z...Ch. 18 - Show how you would accomplish the following...Ch. 18 - Prob. 18.48SPCh. 18 - Prob. 18.49SPCh. 18 - Propose mechanisms for the following reactions.Ch. 18 - Show how you would accomplish the following...Ch. 18 - Show how you would synthesize the following...Ch. 18 - Predict the products formed when cyclohexanone...Ch. 18 - Predict the products formed when...Ch. 18 - Show how you would synthesize octan-2-one from...Ch. 18 - Prob. 18.56SPCh. 18 - Both NaBH4 and NaBD4 are commercially available,...Ch. 18 - When LiAIH4 reduces 3-methylcyclopentanone, the...Ch. 18 - Prob. 18.59SPCh. 18 - Show how you would accomplish the following...Ch. 18 - There are three dioxane isomers 1,2-dioxane,...Ch. 18 - Two structures for the sugar glucose are shown on...Ch. 18 - Prob. 18.63SPCh. 18 - Prob. 18.64SPCh. 18 - Prob. 18.65SPCh. 18 - Prob. 18.66SPCh. 18 - Within each set of structures, indicate which will...Ch. 18 - Prob. 18.68SPCh. 18 - Prob. 18.69SPCh. 18 - Prob. 18.70SPCh. 18 - The UV spectrum of an unknown compound shows...Ch. 18 - a. Simple aminoacetals hydrolyze quickly and...Ch. 18 - The mass spectrum of unknown compound A shows a...Ch. 18 - Prob. 18.74SPCh. 18 - Prob. 18.75SPCh. 18 - Prob. 18.76SPCh. 18 - Prob. 18.77SP
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- H3C 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 be a-brominated by first converting the carboxylic acid to an acid bromide by treatment with PBr3. Following enolization of the acid bromide, Br2 reacts in an a-substitution reaction. Hydrolysis of the acid bromide completes the reaction. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions Br Br зь P-Br Br H₂C H₂C SH Br Brarrow_forwardWrite a mechanism that accounts for the formation of ethyl isopropyl ether as one of the products in the following reaction. CI OEt HCI EtOH Write the mechanism for step one of this reaction. Show lone pairs and formal charges. Only the acidic hydrogen should be drawn out with a covalent bond. Write the mechanism for step two of this reaction (where the product of step one reacts with the solvent, ethanol). Show lone pairs and formal charges. Only the acidic hydrogen should be drawn out with a covalent bond. Write the mechanism for the last step of this reaction (formation of ethyl isopropyl ether). Show lone pairs and formal charges. Only the acidic hydrogen should be drawn out with a covalent bond. CI will act as the base in this reaction.arrow_forwardThe following substances can be prepared by a nucleophilic addition reaction between an aldehyde or ketoneand a nucleophile. Identify the reactants from which they were prepared. If the substance is an acetal, identifythe carbonyl compound and the alcohol; if it is an imine or enamine, identify the carbonyl compound and theamine. You do not have to consider stereochemistry. In cases where there is more than one answer, just giveone. Use Grignard reagents when an organometallic reagent is required. Draw the Grignard reagent as acovalent magnesium bromide.arrow_forward
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