Concept explainers
Interpretation:
A mechanism for the formation of the product in the given reaction is to be suggested.
Concept introduction:
Electrophiles are electron deficient species that have positive or partially positive charge. Lewis acids are electrophiles that accept electron pair.
Nucleophiles are electron rich species that have negative or partially negative charge. Lewis bases are nucleophiles that donate electron pair.
Free radical is an atom, molecule, or ion that has an unpaired electron, which makes it highly chemically reactive.
Substitution reaction: A reaction in which one of the hydrogen atoms of a hydrocarbon or a
Elimination reaction: A reaction in which two substituent groups are detached and a double bond is formed is called elimination reaction.
Addition reaction: It is the reaction in which unsaturated bonds are converted to saturated molecules by the addition of molecules.
In Michael reaction, the conjugate addition of
If the nucleophile is weak, then the conjugate addition is favored.
Base removes acidic hydrogen and forms the enolate ion.
The enolate adds to the
Protonation of the enolate results in the formation of the final product.
In Knoevenagel condensation, a nucleophilic addition of an active methylene takes place which is further followed by dehydration.
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ORGANIC CHEMISTRY-ETEXT REG ACCESS
- Upon hydration of 2-heptyne in the presence of HgSO4 and H2SO4, the two carbons of the triple bond are similarly but not identically substituted resulting in two regioisomeric enols, each of which gives a different ketone. Supply the names of the two enols formed.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_forwardTreatment of a cyclic ketone with diazomethane is a method for accomplishing a ring-expansion reaction. The reaction involves the initial nucleophilic attack by diazomethane on the carbonyl carbon to form a tetrahedral intermediate. Collapse of this intermediate is accompanied by bond migration and loss of N,. For example, treatment of cyclohexanone with diazomethane yields cycloheptanone. CH2N2, ether + N2 Draw the structure of the organic product(s) of the ring expansion of this compound: • You do not have to consider stereochemistry. • You do not have to explicitly draw H atoms. • Do not include lone pairs in your answer. They will not be considered in the grading. • Draw one structure per sketcher Add additional ketchers usina the dron down menu in the bottom right co Previous Nextarrow_forward
- Show how acid derivatives hydrolyze to carboxylic acids under either acidic or basicconditions. Explain why some acid derivatives (amides, for example) require muchstronger conditions for hydrolysis than other derivatives.arrow_forwardThe oxygen in water is primarily (99.8%) 16O, but water enriched with theheavy isotope 18O is also available. When a ketone or aldehyde is dissolved inH2O, the isotopic label becomes incorporated into the carbonyl group: R2CPO H2O n R2CPO H2O. Explain.arrow_forwardGive mechanism asaparrow_forward
- 4) We discussed in class how acetals are formed from a ketone and two equivalents of an alcohol, using an acid catalyst. Alternatively, would a strong base also catalyze (i.e. accelerate) the formation of an acetal? Explain why or why not, in the context of the reaction mechanism and potential intermediates. Naome, MeoH าาาา ← meo ome + Hzoarrow_forwardIn the acid-catalyzed dehydration of 2-methyl-1-propanol, what carbocation would be formed if a hydride shift accompanied cleavage of the carbon–oxygen bond in the alkyloxonium ion? What ion would be formed as a result of a methyl shift? Which pathway do you think will predominate, a hydride shift or a methyl shift?arrow_forwardWhen a methyl ester is hydrolyzed under acidic conditions in H,180, the 180 isotope ends up in the carboxylic acid. When a tert-butyl ester is hydrolyzed under the same conditions, the labeled oxygen ends up in the alcohol product. (a) Propose mechanisms to account for these observations. (b) Explain why each ester undergoes the respective mechanism. CH3 + Но-СНЗ 18 + H180 H ОНarrow_forward
- 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 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 :0: H3C Br Br + :::OH2 Br H₂O H3C Br заarrow_forwardAn example of the McFayden-Stevens reaction is shown below, in which an acyl chloride is converted to an aldehyde. First, benzoyl chloride is reacted with hydrazine, H2NNH2, the product of which is reacted with benzenesulfonyl chloride. The result is a 1-benzoyl-2-benzenesulfonylhydrazide, which, when heated under basic conditions, decomposes into the aldehyde. Provide the detailed mechanism showing the conversion of benzoyl chloride into 1-benzoyl-2-benzenesulfonylhydrazide. H 1. H,NNH2 Na,CO3 CI `SO,C;H5 2. CgHgSO2CI A Benzoyl chloride 1-Benzoyl-2-benzenesulfonylhydrazide Benzaldehydearrow_forwardShow how propanolol can be synthesized from 1-naphthol, epichlorohydrin , and isopropylamine.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning