Prev. Article Next Article Table of Contents

Article

Molecular Modeling to Predict Regioselectivity of Hydration Reactions

Your current credentials do not allow retrieval of the full text.

Purchase the full-text

PDF/HTML,
figures/images,
references and tables,
(where available)

Kate J. Graham , Kathleen Skoglund , Chris P. Schaller , William P. Muldoon and John B. Klassen

Department of Chemistry, College of Saint Benedict, Saint John''s University, St. Joseph, MN 56374-2099

J. Chem. Educ., 2000, 77 (3), p 396

DOI: 10.1021/ed077p396

Publication Date (Web): March 1, 2000

Section:

History, Education, and Documentation

Abstract

In a series of introductory organic chemistry laboratory experiments, students oxidize several isomeric alkenes using acid-catalyzed hydration, oxymercuration/demercuration, and hydroboration to compare the regioselectivity of the different techniques. The product mixtures are subsequently analyzed by GC and IR. To explain the results fully, students use the Spartan 5.0 molecular modeling package to predict the regioselectivity of these hydration reactions. For the acid-catalyzed hydration reaction, they predict the products by calculating the stability of the possible carbocation intermediates using the semiempirical AM1 program. Using semiempirical MNDO calculations, they determine the activation energies for the different possible transition states of the hydroboration reaction. With the activation energies, they can easily predict the preferred products. Semiempirical calculations with a PM3 (tm) basis set to determine the geometry and electrophilicity of the LUMO of the mercuronium ion formed when 1-propene undergoes a reaction with Hg(OAc)₂ allow students to investigate the regioselectivity of the oxymercuration reaction. Using this information, they are able to explain the ratio of products obtained in the laboratory experiment. The calculation and visualization of these reaction pathways greatly enhances students' understanding of the oxidation experiments performed in the lab.

Keywords (Audience):

Second-Year Undergraduate

Keywords (Domain):

Organic Chemistry

Keywords (Pedagogy):

Hands-On Learning / Manipulatives

Keywords (Subject):

Computational Chemistry

View: Hi-Res PDF | PDF w/ Links

Citing Articles

View all 8 citing articles

Citation data is made available by participants in CrossRef's Cited-by Linking service. For a more comprehensive list of citations to this article, users are encouraged to perform a search in SciFinder.

This article has been cited by 8 ACS Journal articles (5 most recent appear below).

Using Molecular Representations To Aid Student Understanding of Stereochemical Concepts
Michael Abraham, Valsamma Varghese, and Hui Tang
Journal of Chemical Education2010 87 (12), 1425-1429
- Using Molecular Representations To Aid Student Understanding of Stereochemical Concepts
  Michael Abraham, Valsamma Varghese, and Hui Tang
  Journal of Chemical Education2010 87 (12), 1425-1429
  Stereochemistry is an important topic in organic chemistry. It is also a difficult topic for students to learn. This study investigated the relative effectiveness on students’ understanding of three kinds of molecular representations of stereochemistry ...
  Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
Using NMR To Probe the Regio- and Stereochemistry of the Hydration of 1-Hexene
Shahrokh Saba, Donald D. Clarke, Christa Iwanoski, and Thomas Lobasso
Journal of Chemical Education2010 87 (11), 1238-1241
- Using NMR To Probe the Regio- and Stereochemistry of the Hydration of 1-Hexene
  Shahrokh Saba, Donald D. Clarke, Christa Iwanoski, and Thomas Lobasso
  Journal of Chemical Education2010 87 (11), 1238-1241
  This undergraduate organic laboratory experiment complements previously described and popular experiments on hydration of 1-hexene where students experimentally establish the Markovnikov regioselectivity of alkene hydration. In this experiment, students ...
  Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
The Question-Driven Laboratory Exercise: A New Pedagogy Applied to a Green Modification of Grignard Reagent Formation and Reaction
Jennifer M. Teixeira, Jessie Nedrow Byers, Marilu G. Perez and R. W. Holman
Journal of Chemical Education2010 87 (7), 714-716
- The Question-Driven Laboratory Exercise: A New Pedagogy Applied to a Green Modification of Grignard Reagent Formation and Reaction
  Jennifer M. Teixeira, Jessie Nedrow Byers, Marilu G. Perez and R. W. Holman
  Journal of Chemical Education2010 87 (7), 714-716
  Experimental exercises within second-year-level organic laboratory manuals typically involve a statement of a principle that is then validated by student generation of data in a single experiment. These experiments are structured in the exact opposite ...
  Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
Regioselectivity in Organic Synthesis: Preparation of the Bromohydrin of alpha-Methylstyrene
Brad Andersh , Kathryn N. Kilby , Meghan E. Turnis and Drew L. Murphy
Journal of Chemical Education2008 85 (1), 102
- Regioselectivity in Organic Synthesis: Preparation of the Bromohydrin of alpha-Methylstyrene
  Brad Andersh , Kathryn N. Kilby , Meghan E. Turnis and Drew L. Murphy
  Journal of Chemical Education2008 85 (1), 102
  In the described experiment, the regiochemical outcome of the addition of "HOBr" to α-methylstyrene is investigated. Although both "classic" qualitative analysis and instrumental techniques are described, the emphasis of this experiment is on the ...
  Abstract | Hi-Res PDF | PDF w/ Links
The State of Organic Teaching Laboratories
Gail Horowitz
Journal of Chemical Education2007 84 (2), 346
- The State of Organic Teaching Laboratories
  Gail Horowitz
  Journal of Chemical Education2007 84 (2), 346
  This review explores the dramatic changes that have taken place in the organic chemistry laboratory course over the last two to three decades. The most significant changes have been in the areas of pedagogy and technology. Significant inroads have been ...
  Abstract | Hi-Res PDF | PDF w/ Links