The m- and p-substituted methyl benzoates listed in the table below were treated with NaOH in dioxane and water. The rate constants of saponification, k, are also listed in the table. Provide structural explanations for the trend observed in the rate constants by comparing the effects of the various substituents on the rate constant. Include all necessary resonance structures in your discussion. of NaOH Dioxane/H,O 35°C Na + CH3OH p- and m-substituted methyl benzoates k (M-'min-1) Methyl p-nitrobenzoate Methyl m-nitrobenzoate Methyl m-chlorobenzoate Methyl m-bromobenzoate 102 63 9.1 8.6 Methyl benzoate Methyl p-methylbenzoate Methyl p-methoxybenzoate Methyl p-aminobenzoate 1.7 0.98 0.42 0.06

The m- and p-substituted methyl benzoates listed in the table below were treated with NaOH in dioxane and water. The rate constants of saponification, k, are also listed in the table. Provide structural explanations for the trend observed in the rate constants by comparing the effects of the various substituents on the rate constant. Include all necessary resonance structures in your discussion. of NaOH Dioxane/H,O 35°C Na + CH3OH p- and m-substituted methyl benzoates k (M-'min-1) Methyl p-nitrobenzoate Methyl m-nitrobenzoate Methyl m-chlorobenzoate Methyl m-bromobenzoate 102 63 9.1 8.6 Methyl benzoate Methyl p-methylbenzoate Methyl p-methoxybenzoate Methyl p-aminobenzoate 1.7 0.98 0.42 0.06

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter22: Reactions Of Benzene And Its Derivatives

Section: Chapter Questions

Problem 22.59P

See similar textbooks

Similar questions

Bromine reacts with alkenes in methanol according to the equation: - When this reaction was carried out with 4-tert-butylcyclohexene, only one isomer was formed with the molecular formula C12H23BrO (80% yield). Which of the following is the structure more reasonable for this compound?. Explain your reasoning through acorresponding mechanism.
The base-promoted rearrangement of an -haloketone to a carboxylic acid, known as the Favorskii rearrangement, is illustrated by the conversion of 2-chlorocyclohexanone to cyclopentanecarboxylic acid. It is proposed that NaOH first converts the a-haloketone to the substituted cyclopropanone shown in brackets and then to the sodium salt of cyclopentanecarboxylic acid. (a) Propose a mechanism for base-promoted conversion of 2-chlorocyclohexanone to the proposed intermediate. (b) Propose a mechanism for base-promoted conversion of the proposed intermediate to sodium cyclopentanecarboxylate.
Starting with benzene, toluene, or phenol as the only sources of aromatic rings, show how to synthesize the following. Assume in all syntheses that mixtures of ortho-para products can be separated into the desired isomer. Q.)2,4,6-Trinitrotoluene (TNT)
Aspirin, or 2-acetoxybenzoic acid, (C9H8O4) is often synthesised from salicylic acid.(i) Sketch and discuss any changes in the number of possible structural conformations ofaspirin relative to those of salicylic acid. (ii) Re-draw the structure predicted to be the lowest energy conformation of aspirin,indicating any expected stabilising and destabilising interactions. Justify your choice.
On being heated with a solution of sodium ethoxide in ethanol, compound A (C7H15Br) produced a mixture of two alkenes B and C, each of which had the molecular formula C7H14. Catalytic hydrogenation of major isomer B or minor isomer C gave only 3-ethylpentane. Suggest structures and mechanisms for compounds A, B, and C consistent with these observations.
A certain hydrocarbon, C7H10, yields the two products shown below upon oxidative cleavage with KMnO4/H3O+ . Deduce the structure of the hydrocarbon.
Suppose you are told that each reaction is a substitution reaction but are not told the mechanism. Describe how you could conclude from the structure of the haloalkane, the nucleophile, and the solvent that each reaction is an SN2 reaction.
(10pts) Compound A, C10H16, was found to be optically active. On catalytic reduction over a palladium catalyst, 2 equivalents of hydrogen were absorbed, yielding compound B, CioH2o. On ozonolysis of A, two fragments were obtained. One fragment was identified as acetic acid (CHCOOH). The other fragment, compound C, was an optically active carboxylic acid, C8H14O2. Write reactions, and draw the correct structures for A-C, explain your answer in detail.
(i) Name, draw and describe the organic product of the reaction between 2-methylbut-1-ene and H2O in the presence of H2SO4 and provide a clear rationale as to why this is the major product of the reaction. (ii) The elimination reaction between 2-bromobutane and NaOCH2CH3 gives two organic products. Draw a mechanism for the reaction which produces the major organic elimination product and provide a rationale as to why that is the major product.
The reaction of 1-iodopropane with potassium thiocyanate (KSCN) in certain solvents results in the formation of two isomeric products, propylthiocyanate and propylisothiocyanate (see scheme below), via the SN2 reaction mechanism. Attempts to prepare a similar mixture of these same isomeric products (propylthiocyanate and propylisothiocyanate) starting from 1-propene is illustrated below. Despite the strong acidity of thiocyanic acid (recall pKa = 1.1), this addition reaction does not lead to either of the products indicated. Based on your knowledge of alkene addition reactions, explain this experimental result.
we know that ethers, such as diethyl ether and tetrahydrofuran, are quite resistant to the action of dilute acids and require hot concentrated HI or HBr for cleavage. However, acetals in which two ether groups are linked to the same carbon undergo hydrolysis readily, even in dilute aqueous acid. How do you account for this marked difference in chemical reactivity toward dilute aqueous acid between ethers and acetals?
Bromine reacts with alkenes in methanol according to the equation (see image 1). When this reaction was carried out with 4-tert-butylcyclohexene, only one isomer was formed with the molecular formula C12H23BrO (80% yield) a) Which of the following is the structure more reasonable for this compound? (see image 2) b) Explain your reasoning through a corresponding mechanism