|
|
| Home > JCE Print > Journal of Chemical Education > Issues >
2005
>
March
> |
|
In the Laboratory
|
|
|
|
The Rearrangement of an Allylic Dithiocyanate: An Experiment for Organic or Physical Chemistry Using NMR Analysis
|
David W. Emerson, Spencer M. Steinberg, and Richard L. Titus
Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, NV 89154-4003
|
|
March 2005
Vol. 82 No. 3
p. 466
|
|
|
|
|
|
|
| Abstract |
|
An experiment suitable for students who have taken either organic chemistry or organic and physical chemistry is described. The simple preparation and molecular rearrangement of thiocyanic acid, 2-methylene-1,3-propanediyl ester to 1-propene, (3-isothiocyanato-2-isothiocyanatomethyl) occurs readily in the temperature range of 65–90°C and progress of the reaction is readily tracked by proton NMR. The buildup and decline of the intermediate, thiocyanic acid, 2-(isothiocyanatomethyl)-2-propenyl ester, is readily seen. Start and stop methods for conducting the reaction in simple apparatus external to the NMR instrument are described thus making the experiment suitable for several students to do in a limited period of time without tying up the NMR for long periods. A controlled temperature probe for the NMR instrument is not needed. Advanced students can determine rate constants for the reactions, compute activation parameters, and observe solvent effects.
|
| Supplement |
Experimental details, rate studies, and NMR data are available.
|
 Contents |
Folder JCE2005p0466W containing JCE2005p0466W.doc (Microsoft Word) and JCE2005p0466W.cdx (ChemDraw).
|
| Download |
|
|
| More Information |
Citation |
Emerson, David W.; Steinberg, Spencer M.; Titus, Richard L. J. Chem. Educ. 2005 82 466.
|
Keywords |
Kinetics; Laboratory Instruction; Mechanisms of Reactions; NMR Spectrometry; Organic Chemistry; Physical Chemistry; Quantitative Analysis
|
History |
Created:
Last Updated: |
February 2, 2005
February 16, 2005
|
|
|
|
|
|
| Home > JCE Print > Journal of Chemical Education > Issues >
2005
>
March
> Page
466
|
|
|
| JCE HS CLIC |
|
Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.
|
| Contributions Welcome |
| JCE welcomes your submission |
| Advertisers |
| In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first. |
| Be An Ambassador |
| Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants. |
|
