A "condensation" reaction involves the loss of a small neutral molecule as a follow-up step to an addition reaction. The product is an a,ß-unsaturated aldehyde (or ketone). (*In aldol condensations, the small neutral molecule is water.) Which of the three products shown is the correct aldol condensation products of the reaction shown. Write the mechanism for the dehydration step. Assume the reaction mixture still contains catalytic base. OH NaOH or H adol addition = enolates + aldehyde LOHY Condensation (OH or (H₂O + OH

A "condensation" reaction involves the loss of a small neutral molecule as a follow-up step to an addition reaction. The product is an a,ß-unsaturated aldehyde (or ketone). (*In aldol condensations, the small neutral molecule is water.) Which of the three products shown is the correct aldol condensation products of the reaction shown. Write the mechanism for the dehydration step. Assume the reaction mixture still contains catalytic base. OH NaOH or H adol addition = enolates + aldehyde LOHY Condensation (OH or (H₂O + OH

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter17: Alcohols And Phenols

Section17.SE: Something Extra

Problem 71AP: A problem often encountered in the oxidation of primary alcohols to acids is that esters are...

See similar textbooks

Similar questions

complete the following syntheses
The following molecule undergoes an intramolecular reaction in the presence of pyrrolidinium acetate, the protonated form of pyrrolidine. Draw the product of this reaction, assuming that a dehydration reaction takes place.
A problem often encountered in the oxidation of primary alcohols to acids is that esters are sometimes produced as by-products. For example, oxidation of ethanol yields acetic acid and ethyl acetate: Propose a mechanism to account for the formation of ethyl acetate. Take into account the reversible reaction between aldehydes and alcohols:
Hydroxylamine, H2NOH, has both an OH functional group and an NH2 functional group, so it can feasibly undergo reaction with a ketone or an aldehyde to produce either an acetal or an imine-like compound called an oxime. (a) Draw each of these mechanisms for the reaction of hydroxylamine with acetone. (b) Which is the major product? Hint: Which step decides the outcome?
Predict the products of aldol condensation, followed by dehydration, of the followingketones and aldehydes. c) cyclohexanone
Acetal formation must be catalyzed by an acid. Explain why it cannot be catalyzed by CH3O-.
In a Wittig reaction, a ketone or aldehyde reacts as an electrophile with a nucleophile called a Wittig reagent (or phosphonium ylide) to produce an alkene. The Wittig reagent is commonly synthesized first in a two-step process beginning with an alkyl halide, then reacted with the carbonyl compound. In this problem, you'll explore the mechanism of a multi-step synthesis to make an alkene using the Wittig approach.
2 H3C H3C H C→XT OH H3C The aldol reaction is a carbonyl condensation reaction between two carbonyl partners and involves a combination of nucleophilic addition and a-substitution steps. One partner is converted into an enolate ion nucleophile and adds to the electrophilic carbonyl group of the second partner. In the classic aldol reaction, the carbonyl partners are aldehydes or ketones, although aldehydes are more reactive. The product is a ß-hydroxy carbonyl compound. base :0: OH H H Under reaction conditions slightly more vigorous than those employed for the aldol reaction, the ß-hydroxyl group is eliminated in an E1cB dehydration to give an a,ß-unsaturated carbonyl compound. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instruct ns H3C heat OH H3C :0: H + H₂O H
How many elimination products will be formed in the following reaction?
Draw the structure of the hydroxyaldehyde product from the self-aldol reaction of each of the following aldehydes: (a) propanal; (b) phenylethanal; (c) 3-phenylpropanal; (d) benzaldehyde.
Acetal derivatives of aldehydes and ketones are prepared by an acid-catalyzed dehydration reaction with alcohols or diols. Using more pictures than words, draw a reaction and a mechanism that shows the formation of acetal.
Indicates the reagents needed to carry out the following reactions if there is more than one possible reagent, indicate it