Prev. Article Next Article Table of Contents

Article

Use of Optical Rotation and NMR Signal Counting To Identify Common Aldoses

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

Purchase the full-text

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

John Almy

Chemistry Department, California State University, Stanislaus, Turlock, CA 95382

J. Chem. Educ., 2004, 81 (5), p 708

DOI: 10.1021/ed081p708

Publication Date (Web): May 1, 2004

Section:

History, Education, and Documentation

Abstract

An inexpensive, small scale experiment for second semester organic students describes the unambiguous identification of a common aldose "unknown" from five possible candidates: glucose, mannose, galactose, arabinose, or xylose. The aldose is first reduced to an alditol to permit possible symmetry in the molecule. The alditol is then converted to its peracetate for improved crystallization and analysis by polarimetry and NMR. Without referring to melting points in the literature or published spectra, students examine the symmetry properties of each candidate's alditol peracetate to determine which structure fits the rotational data and NMR spectra. As an option, the ketoses, sorbose and fructose, can be similarly reduced and acetylated. Each will produce peracetate mixtures that can be identified by NMR using the information obtained from the aldoses, again without the need for published data.

Keywords (Audience):

Second-Year Undergraduate

Keywords (Domain):

Organic Chemistry

Keywords (Pedagogy):

Hands-On Learning / Manipulatives

Keywords (Subject):

NMR Spectroscopy

View: Hi-Res PDF | PDF w/ Links

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 1 ACS Journal articles (1 most recent appear below).

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