Organic Chemistry As a Second Language: First Semester Topics
Organic Chemistry As a Second Language: First Semester Topics
4th Edition
ISBN: 9781119110668
Author: David R. Klein
Publisher: WILEY
Question
Book Icon
Chapter 12.5, Problem 12.27P
Interpretation Introduction

Interpretation:

The reagent that has to be used to achieve the given transformation has to be identified.

Concept Introduction:

Alkynes are the compounds that contain a triple bond between two carbon atoms.  The carbon atom present in the triple bond is sp hybridised.  Due to this, the geometry of alkyne will be linear.  Terminal alkyne are the one which has a proton attached to the triple bond and internal alkyne are the one in which there are no protons attached to the triple bond.

Organic Chemistry As a Second Language: First Semester Topics, Chapter 12.5, Problem 12.27P , additional homework tip  1

Hydration of Alkynes:

Alkynes undergo hydration reaction in presence of acid and mercuric sulfate as catalyst to form an enol as the initial product.  The formed enol gets converted fast into keto due to keto-enol tautomerism.  Ketone and enol are constitutional isomers.  If the alkyne under consideration is a terminal alkyne, then methyl ketone will be the product that is obtained.  The general scheme for hydration of alkyne can be given as shown below,

Organic Chemistry As a Second Language: First Semester Topics, Chapter 12.5, Problem 12.27P , additional homework tip  2

Hydration of alkynes through the method said above is a Markovnikov addition.

Hydroboration-oxidation of Alkynes:

Alkynes undergo hydroboration-oxidation reaction in presence of dialkyl borane, hydrogen peroxide and sodium hydroxide to form an enol as the initial product.  The formed enol gets converted fast into keto due to keto-enol tautomerism.  Ketone and enol are constitutional isomers.  If the alkyne under consideration is a terminal alkyne, then aldehyde will be the product that is obtained.  The general scheme for hydration of alkyne can be given as shown below,

Organic Chemistry As a Second Language: First Semester Topics, Chapter 12.5, Problem 12.27P , additional homework tip  3

Hydroboration-oxidation of alkynes through the method said above is an anti-Markovnikov addition.

Acid catalyzed hydration of alkynes installs the carbonyl group at the C2 position, while hydroboration-oxidation installs the carbonyl group in C1 position.

Organic Chemistry As a Second Language: First Semester Topics, Chapter 12.5, Problem 12.27P , additional homework tip  4

Blurred answer
Knowledge Booster
Background pattern image
Recommended textbooks for you
Text book image
Chemistry
Chemistry
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning
Text book image
Chemistry
Chemistry
ISBN:9781259911156
Author:Raymond Chang Dr., Jason Overby Professor
Publisher:McGraw-Hill Education
Text book image
Principles of Instrumental Analysis
Chemistry
ISBN:9781305577213
Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:Cengage Learning
Text book image
Organic Chemistry
Chemistry
ISBN:9780078021558
Author:Janice Gorzynski Smith Dr.
Publisher:McGraw-Hill Education
Text book image
Chemistry: Principles and Reactions
Chemistry
ISBN:9781305079373
Author:William L. Masterton, Cecile N. Hurley
Publisher:Cengage Learning
Text book image
Elementary Principles of Chemical Processes, Bind...
Chemistry
ISBN:9781118431221
Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:WILEY