Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 27: Problem 51

How would you synthesize \((E)\) - and \((Z)\) -3-heptene from acetylene and any other chemicals?

Short Answer

Expert verified
(E)-3-heptene can be synthesized from acetylene by shooting chain extension through coupling reactions, forming a double bond via dissolving metal reduction. (Z)-3-heptene synthesis is similar, but the double bond formation step must employ a Lindlar's catalyst.

Step by step solution

01

Extension of the Carbon Chain

Alkyne acetylene needs to be extended to a 7-carbon chain. This could be achieved by undergoing a sequence of coupling reactions with an appropriate alkyl halide using sodium amide (NaNH2) as a base in liquid ammonia. The process aims for a C-C bond formation.
02

Establishment of the Double Bond

After achieving a 7-carbon chain, a double bond needs to be introduced at the 3rd carbon. This could be achieved by partial reduction of the alkyne to an alkene by using the Lindlar's catalyst which just reduces the triple bond to a double bond, not a single bond.
03

Stereochemistry Control

E/Z isomerism refers to the stereochemistry of double bonds. In general, Lindlar's catalyst gives the (Z)-alkene and dissolving metal reduction gives the (E)-alkene. Therefore, (E)-3-heptene would be generated from dissolving metal reduction while (Z)-3-heptene would be synthesized using Lindlar's catalyst. This step includes the portion of controlling for E/Z stereochemistry.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Write the formulas of the products formed from the reaction of 2 -butene with each of the following substances: (a) \(\mathrm{H}_{2} ;\) (b) \(\mathrm{Cl}_{2} ;\) (c) \(\mathrm{HCl} ;\) (d) \(\mathrm{H}_{2} \mathrm{O}\) (in acid).

Write equations for the substitution reaction of \(n\) -bromobutane, a typical primary haloalkane, with the following reagents: (a) \(\mathrm{NaOH} ;\) (b) \(\mathrm{NH}_{3} ;\) (c) \(\mathrm{NaCN}\) (d) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{ONa}\).

Indicate the principal product(s) you would expect in (a) treating \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}=\mathrm{CH}_{2}\) with dilute \(\mathrm{H}_{2} \mathrm{SO}_{4}(\mathrm{aq})\) (b) exposing a mixture of chlorine and propane gases to ultraviolet light; (c) heating a mixture of isopropyl alcohol and benzoic acid; (d) oxidizing sec-butyl alcohol with \(\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}\) in acidic solution.

Answer the following questions for this E2 reaction: $$\begin{aligned} \mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{Br}+\mathrm{NaOH} & \longrightarrow \mathrm{CH}_{3} \mathrm{CH}= \mathrm{CH}_{2}+\mathrm{NaBr}+\mathrm{H}_{2} \mathrm{O} \end{aligned}$$ (a) What is the rate expression for the reaction? (b) Draw the reaction profile for the reaction. Label all parts. Assume that the products are lower in energy than the reactants. (c) What is the effect on the rate of the reaction of doubling the concentration of \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{Br} ?\) (d) What is the effect on the rate of the reaction of halving the concentration of \(\mathrm{NaOH} ?\)

Explain the important distinctions between each pair of terms: (a) base and nucleophile; (b) \(\alpha\) carbon and \(\beta\) carbon; (c) polar protic solvent and polar aprotic solvent; (d) carbocation and radical.
See all solutions

Recommended explanations on Chemistry Textbooks

Physical Chemistry

Read Explanation

Chemical Analysis

Read Explanation

Chemical Reactions

Read Explanation

Ionic and Molecular Compounds

Read Explanation

Organic Chemistry

Read Explanation

Kinetics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free