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
- Provide the mechanism for this reaction (include arrow pushing) ОН 2-lodobenzoic acid K2S2O8 H2SO4 ОН OSO3H ОН 양 diphenyliodonium-2-Carboxylate benzynearrow_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_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_forward
- (b) Answer the following questions based on the compounds below. Jawab soalan berikut berdasarkan kepada sebatian di bawah. Br -Br A в (i) Which compound has the lower boiling point? Explain your answer. Sebatian manakah yang mempunyai takat didih yang lebih rendah? Terangkan jawapan anda. (ii) Draw the SN1 mechanism for the reaction of compound B with sodium hydroxide, NaOH. Lukiskan mekanisma SN1 bagi tindak balas antara sebatian B dengan natrium hidroksida, NaOH. (ii) Arrange the following compounds in increasing order of acidity. Susunkan sebatian berikut mengikut tertib menaik keasidannya. он HO, HO, Earrow_forwardThe following compound, 2-hydroxycycloheptatrienone, does not give all the usual carbonyl group reactions. (i) Explain this apparent anomaly. Furthermore, explain the significant difference between the relative stability of this compound and its 3- and 4-hydroxy isomers. (ii) What would you expect to be the influence of adding (a) a nitro group as a substituent on the 7-membered ring or (b) an alkyl group, on the degree of aromaticity of the above compound. (iii) Based on your understanding of the hydrogen bonding concept, which isomer would you expect to have a higher m.p, (assuming they are both solids) between 2- and 4- hydroxycycloheptatrienone? Explain your choice.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
- An elimination step is involved in the synthesis of aromatic amino acids. We can also envision this occurring in a laboratory setting with a strong base. Provide a 1 step mechanism for this decarboxylation reaction. Note: under strongly basic conditions, hydroxide is a reasonable leavinggroup.arrow_forwardH₂C 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_forwardA ketone undergoes acid-catalyzed bromination, acid-catalyzed chlorination, racemization, (see page 408)and acid-catalyzed deuterium exchange at the a-carbon. All of these reactions have similar rate constants.What does this tell you about the mechanisms of these reactions?arrow_forward
- An 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_forwardAlkenes can be converted into alcohols by acid-catalyze addition of water. Predict the major alcohol product from this alkene below.arrow_forwardComplete the statements by providing the reagents necessary to complete each step of the synthesis. Ketone reacted with CO₂H and then yielded a derivative, which was treated with 1) (i) C6H5MgBr (ii) H3O+ 2) (i) DIBAL-H (ii). H3O+ 3) Sia2BH,H202, NaOH 4) CH2N2 (diazamethane) CO₂C2H5 5) PCC (an oxidant) 6) H2SO4, H2O, heat 7) HgSO4/ H2SO4 8) C₂H5OH, H3O*, heat TABLE OF REAGENTS to form an unsaturated carboxylic acid, treatment with to yield unsaturated aldehyde as the final product. CHO MacBook Air 9) C6H5 CH2 P(C6H5)3; NaOH 10) PCC (an oxidant) 11) NaCN, H₂SO4 12) PhCH2CHO, H3O*arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning