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Journal Articles: 48 results
Borohydride Reduction of Estrone  Animesh Aditya, David E. Nichols, and G. Marc Loudon
This experiment presents a guided-inquiry approach to the demonstration of diastereoselectivity using chiral hindered ketones that undergo facile reduction with sodium borohydride. The resulting diastereomeric estradiols can be analyzed and differentiated by thin-layer chromatography and melting point.
Aditya, Animesh; Nichols, David E.; Loudon, G. Marc. J. Chem. Educ. 2008, 85, 1535.
Aldehydes / Ketones |
Diastereomers |
IR Spectroscopy |
Microscale Lab |
Stereochemistry |
Steroids |
Thin Layer Chromatography
Frank Westheimer's Early Demonstration of Enzymatic Specificity  Addison Ault
Reviews one of the most significant accomplishments of one of the most respected chemists of the 20th centurya series of stereospecific enzymatic oxidation and reduction experiments that led chemists to recognize enantiotopic and diastereotopic relationships of atoms, or groups of atoms, within molecules.
Ault, Addison. J. Chem. Educ. 2008, 85, 1246.
Asymmetric Synthesis |
Bioorganic Chemistry |
Catalysis |
Chirality / Optical Activity |
Enantiomers |
Enzymes |
Isotopes |
Nucleophilic Substitution |
Oxidation / Reduction |
Stereochemistry
Evaluating Mechanisms of Dihydroxylation by Thin-Layer Chromatography  Benjamin T. Burlingham and Joseph C. Rettig
Presents a microscale experiment in which cyclohexene is dihydroxylated under three sets of conditions and the products determined through thin-layer chromatography. Teams of students evaluate proposed mechanisms for each dihydroxylation in light of the data collected.
Burlingham, Benjamin T.; Rettig, Joseph C. J. Chem. Educ. 2008, 85, 959.
Addition Reactions |
Alkenes |
Diastereomers |
Mechanisms of Reactions |
Microscale Lab |
Stereochemistry |
Synthesis |
Thin Layer Chromatography
The Same and Not the Same: Chirality, Topicity, and Memory of Chirality  Wolfgang H. Kramer and Axel G. Griesbeck
Describes a simple molecular approach that aids students in learning stereochemical terms, definitions, and concepts, particularly when chemical structures are drawn in two dimensions.
Kramer, Wolfgang H.; Griesbeck, Axel G. J. Chem. Educ. 2008, 85, 701.
Chirality / Optical Activity |
Stereochemistry
Mosher Amides: Determining the Absolute Stereochemistry of Optically-Active Amines  Damian A. Allen, Anthony E. Tomaso, Jr., Owen P. Priest, David F. Hindson, and Jamie L. Hurlburt
In this experiment, teams of students are given an optically-pure amine of known structure but unknown stereochemistry. Different teams derivatize samples of the amine with (R) and (S) conformations of Mosher's acid chloride. The resulting diastereomers are analyzed by NMR to determine the absolute configuration of the initial, unknown amine.
Allen, Damian A.; Tomaso, Anthony E., Jr.; Priest, Owen P.; Hindson, David F.; Hurlburt, Jamie L. J. Chem. Educ. 2008, 85, 698.
Amides |
Chirality / Optical Activity |
Chromatography |
Diastereomers |
Microscale Lab |
NMR Spectroscopy |
Stereochemistry
The Meaning of Meso  Addison Ault
The original use of the prefix "meso" was to refer to an optically inactive, non-resolvable member of a set of stereoisomers, some of which were optically active.
Ault, Addison. J. Chem. Educ. 2008, 85, 441.
Chirality / Optical Activity |
Stereochemistry
A Knoevenagel Initiated Annulation Reaction Using Room Temperature or Microwave Conditions  A. Gilbert Cook
The product of a Knoevenagel initiated annulation reaction is identified through a guided prelab exercise of the synthesis of the Hagemann ester, and then through the analysis of GCMS, NMR, and IR spectra. The stereochemistry of the product is determined through the NMR spectrum and Karplus curve, and the student is required to write a mechanism for the reaction.
Cook, A. Gilbert. J. Chem. Educ. 2007, 84, 1477.
Aldehydes / Ketones |
Conformational Analysis |
Gas Chromatography |
IR Spectroscopy |
Mass Spectrometry |
Mechanisms of Reactions |
NMR Spectroscopy |
Stereochemistry |
Synthesis
Precision in Stereochemical Terminology  LeRoy G. Wade, Jr.
This article recommends that instructors use the precise terms asymmetric carbon atom and chirality center when they apply, and use the broader term stereocenter only when there is a need to include stereogenic atoms that are not chirality centers.
Wade, LeRoy G., Jr. J. Chem. Educ. 2006, 83, 1793.
Chemical Technicians |
Diastereomers |
Enantiomers |
Stereochemistry |
Nomenclature / Units / Symbols |
Chirality / Optical Activity
Diastereoselectivity in the Reduction of α-Hydroxyketones. An Experiment for the Chemistry Major Organic Laboratory  David B. Ball
Describes a research type, inquiry-based project where students synthesize racemic ahydroxyketones using umpolung, a polarity-reversal approach; investigate chelating versus non-chelating reducing agents; and determine the diastereoselectivity of these reducing processes by NMR spectroscopy.
Ball, David B. J. Chem. Educ. 2006, 83, 101.
Addition Reactions |
Aldehydes / Ketones |
Chirality / Optical Activity |
Chromatography |
Conferences |
Constitutional Isomers |
Enantiomers |
NMR Spectroscopy |
Stereochemistry |
Synthesis |
Conformational Analysis
Use of Enzymes in Organic Synthesis: Reduction of Ketones by Baker's Yeast Revisited  James Patterson and Snorri Th. Sigurdsson
The undergraduate organic laboratory Bakers Yeast Reduction of Ethyl Acetoacetate has been improved in two different ways. First, the addition of small quantities of hexane to the aqueous yeast system along with an improved workup protocol has dramatically increased the yield and reproducibility of the ketone conversion to the corresponding alcohol with a high enantiomeric excess. Second, the enantiomeric excess of the alcohol product was ascertained by coupling the alcohol mixture with a chiral acid and analyzing the resulting mixture of diastereomeric esters by proton NMR.
Patterson, James; Sigurdsson, Snorri Th. J. Chem. Educ. 2005, 82, 1049.
Enzymes |
NMR Spectroscopy |
Stereochemistry |
Gas Chromatography |
Synthesis
An Engaging Illustration of the Physical Differences among Menthol Stereoisomers  Edward M. Treadwell and T. Howard Black
The differences and similarities in the physical behavior of enantiomers and diastereomers can easily be demonstrated using the commercial stereoisomers (-)-menthol, (+)-menthol, (+)-isomenthol, and (+)-neomenthol. Thin-layer chromatography and melting point determinations clearly show that diastereomers have different physical properties from enantiomers and each other, but that enantiomers have identical physical properties in achiral environments. By obtaining a mixed melting point and optical rotations the difference in enantiomers can be observed.
Treadwell, Edward M.; Black, T. Howard. J. Chem. Educ. 2005, 82, 1046.
Chirality / Optical Activity |
Stereochemistry |
Thin Layer Chromatography |
Diastereomers |
Enantiomers |
Physical Properties
Enantiomeric Resolution of (±)-Mandelic Acid by (1R,2S)-(–)-Ephedrine. An Organic Chemistry Laboratory Experiment Illustrating Stereoisomerism  Marsha R. Baar and Andrea L. Cerrone-Szakal
There has been an increasing need, particularly in the pharmaceutical industry, to prepare chiral substances in single-isomer form. A chiral technique that makes an excellent introductory organic chemistry experiment is enantiomeric resolution. The classical resolution of ()-mandelic acid using the chiral amine, (1R,2S)-()-ephedrine, was adapted for use in introductory organic chemistry lab curricula.
Baar, Marsha R.; Cerrone-Szakal, Andrea L. J. Chem. Educ. 2005, 82, 1040.
Acids / Bases |
Chirality / Optical Activity |
Separation Science |
Stereochemistry |
Diastereomers |
Enantiomers
The Darzens Condensation: Structure Determination through Spectral Analysis and Understanding Substrate Reactivity  R. David Crouch, Michael S. Holden, and Candice A. Romany
The Darzens condensation involves two steps that are typically included in the sophomore organic curriculum: an aldol reaction followed by an intramolecular nucleophilic substitution.
Crouch, R. David; Holden, Michael S.; Romany, Candice A. J. Chem. Educ. 2004, 81, 711.
NMR Spectroscopy |
Synthesis |
Stereochemistry |
Mechanisms of Reactions |
Aldehydes / Ketones
Diastereoselective Synthesis of a Strawberry Flavoring Agent by Epoxidation of Ethyl trans-b-Methylcinnamate  Gayle J. Pageau, Rodwell Mabaera, Kathryn M. Kosuda, Tamara A. Sebelius, Ali H. Ghaffari, Kenneth A. Kearns, Jean P. McIntyre, Tina M. Beachy, and Dasan M. Thamattoor
Synthesis of the "strawberry aldehyde" epoxide, a well-known food and perfume additive.
Pageau, Gayle J.; Mabaera, Rodwell; Kosuda, Kathryn M.; Sebelius, Tamara A.; Ghaffari, Ali H.; Kearns, Kenneth A.; McIntyre, Jean P.; Beachy, Tina M.; Thamattoor, Dasan M. J. Chem. Educ. 2002, 79, 96.
Molecular Modeling |
NMR Spectroscopy |
Synthesis |
Stereochemistry |
Epoxides |
Consumer Chemistry |
Food Science
"Dishing Out" Stereochemical Principles  Harold Hart
Demonstrating the concepts of chiral centers and enantiomers using plastic dishes.
Hart, Harold. J. Chem. Educ. 2001, 78, 1632.
Chirality / Optical Activity |
Molecular Modeling |
Stereochemistry |
Molecular Properties / Structure |
Enantiomers
Diastereoselective Synthesis of (+/-)-1,2-Diphenyl-1,2-propanediol. A Discovery-Based Grignard Reaction Suitable for a Large Organic Lab Course  James A. Ciaccio, Roxana P. Bravo, Antoinette L. Drahus, John B. Biggins, Rosalyn V. Concepcion, and David Cabrera
An experiment that probes the diastereoselectivity of the reaction between a Grignard reagent and a common, inexpensive alpha-chiral ketone; introduces students to pi-facial discrimination by having them establish the stereochemical course of kinetically controlled nucleophilic addition to a carbonyl.
Ciaccio, James A.; Bravo, Roxana P.; Drahus, Antoinette L.; Biggins, John B.; Concepcion, Rosalyn V.; Cabrera, David. J. Chem. Educ. 2001, 78, 531.
Mechanisms of Reactions |
Synthesis |
Organometallics |
Stereochemistry |
Grignard Reagents |
Aldehydes / Ketones
Introducing Stereochemistry to Non-science Majors  Hannia Luján-Upton
Two exercises to introduce concepts associated with stereochemistry such as "sameness", superimposability, chirality, enantiomers, optical activity, polarimetry, and racemic mixtures; one compares chirality in hands with the achiral nature of two textbooks, the other involves a murder mystery.
Luján-Upton, Hannia. J. Chem. Educ. 2001, 78, 475.
Chirality / Optical Activity |
Stereochemistry |
Nonmajor Courses |
Molecular Properties / Structure
Enantiomeric and Diastereoisomeric Relationships: A Practical Approach  V. Durieu, G. Martiat, M. Ch. Vandergeten, F. Pirsoul, F. Toubeau, and Agnès Van Camp
An experiment in organic chemistry in which the students prepare, purify, and characterize optical isomers. The three optical isomers of the bisoxalamides obtained by the reaction of racemic 1-phenylethylamine with diethyloxalate are separable by flash chromatography into the racemic mixture of (R,R) + (S,S) oxalamides and the (R,S) meso compound.
Durieu, V.; Martiat, G.; Vandergeten, M. Ch.; Pirsoul, F.; Toubeau, F.; Van Camp, Agnès. J. Chem. Educ. 2000, 77, 752.
Molecular Properties / Structure |
Stereochemistry |
Separation Science |
Enantiomers |
Diastereomers |
Chirality / Optical Activity |
Synthesis
Synthesis and Separation of a Diastereomeric Sulfonium Ion by Capillary Zone Electrophoresis  Francisco A. Valenzuela, Thomas K. Green, and Darwin B. Dahl
An undergraduate laboratory exercise utilizing capillary zone electrophoresis in the analysis of the student-synthesized sulfonium ion sec-butylmethyl-p-tolylsulfonium tetrafluoroborate is presented. The sulfonium ion contains two stereogenic centers and thereby yields four optical isomers.
Valenzuela, Francisco A.; Green, Thomas K.; Dahl, Darwin B. J. Chem. Educ. 1998, 75, 1590.
Electrophoresis |
Stereochemistry |
NMR Spectroscopy |
Diastereomers |
Separation Science |
Synthesis
Stereowordimers-Minding Your P's and Q's  Edward G. Neeland
The use of words having different colored sides is a excellent way to introduce stereochemical concepts that might not be easily grasped when using molecular examples. We have found that concepts such as enantiomers, diastereomers, identical molecules, chirality, achirality, mirror planes of symmetry, and internal planes of symmetry are readily understood by students when using stereowordimer examples.
Neeland, Edward G. J. Chem. Educ. 1998, 75, 1573.
Stereochemistry |
Diastereomers |
Enantiomers |
Molecular Properties / Structure
Models and Molecules - A Workshop on Stereoisomers  Robert W. Baker, Adrian V. George, and Margaret M. Harding
A molecular model workshop aimed at first year university undergraduates has been devised to illustrate the concepts of organic stereochemistry. The students build models to teach the relationship within, and between, conformational isomers, enantiomers, and diastereomers.
Baker, Robert W.; George, Adrian V.; Harding, Margaret M. J. Chem. Educ. 1998, 75, 853.
Molecular Properties / Structure |
Stereochemistry |
Molecular Modeling |
Enantiomers |
Diastereomers
Discovery-Based Stereochemistry Tutorials Available on the World Wide Web  Abby L. Parrill and Jacquelyn Gervay
The WWW offers the ability to develop interactive, discovery-based tutorials for use as study tools, and multimedia offers significant improvements in the display of three-dimensional objects. As part of a chemical education research program, three stereochemistry tutorials were developed to capitalize on these advantages.
Parrill, Abby L.; Gervay, Jacquelyn. J. Chem. Educ. 1997, 74, 329.
Stereochemistry |
Molecular Properties / Structure |
Molecular Modeling
Diastereospecific Synthesis of an Epoxide: An Introductory Experiment in Organic Synthetic and Mechanistic Chemistry  James A. Ciaccio
A two-step epoxide synthesis that can be presented to students in the form of two mechanistic "puzzles" that probe the stereoselectivity of two important reactions: halohydrin formation from alkenes and epoxide formation via intramolecular Williamson ether synthesis.
Ciaccio, James A. J. Chem. Educ. 1995, 72, 1037.
Stereochemistry |
Molecular Properties / Structure |
Mechanisms of Reactions |
Synthesis |
Epoxides |
Alkenes
Incorporating Heterotopicity into Organic Chemistry  Thall, Edwin
This paper reviews topological relationships and suggests how to incorporate heterotopic concepts into the contemporary chemistry curriculum.
Thall, Edwin J. Chem. Educ. 1994, 71, 1034.
Stereochemistry |
Crystal Field / Ligand Field Theory
The square knot and the granny knot: An analogy for diastereomers.  Tavernier, Dirk.
Few of the diastereomorphs generated by joining two man-made chiral objects have different names; the author is aware of just one example - the square knot and the granny knot.
Tavernier, Dirk. J. Chem. Educ. 1992, 69, 627.
Diastereomers |
Molecular Properties / Structure |
Stereochemistry |
Chirality / Optical Activity
Representing isomeric structures: Five applications.  Thall, Edwin.
Five applications of a new method that the author calls Representing Isomeric Structures, in which arrows are used to point to unique sites on the carbon skeleton to represent functional groups.
Thall, Edwin. J. Chem. Educ. 1992, 69, 447.
Stereochemistry |
Molecular Properties / Structure |
Chirality / Optical Activity |
Enantiomers
Natural and unnatural models for illustrating chirality at two centers  Nave, Paul M.
Some clever suggestions for models that will help students understand chirality better. Puppies and a two-headed goat are involved.
Nave, Paul M. J. Chem. Educ. 1991, 68, 1028.
Stereochemistry |
Chirality / Optical Activity |
Enantiomers
The stereochemistry of additions to trans-anethole  McGahey, Lawrence
Trans-anethole is brominated with pyridinium bromide perbromide in dichloromethane.
McGahey, Lawrence J. Chem. Educ. 1990, 67, 554.
Addition Reactions |
Stereochemistry |
Mechanisms of Reactions |
Alkenes |
Diastereomers |
Enantiomers
Magnetic nonequivalence in 1,2-disubstituted ethanes: An organic experiment in NMR spectroscopy  Colborn, Robert E.
The main purpose of this experiment is to help students consider the various couplings available in organic molecules and determine whether specific groups will have identical chemical shifts or not.
Colborn, Robert E. J. Chem. Educ. 1990, 67, 438.
NMR Spectroscopy |
Stereochemistry
Molecular mechanics as an organic chemistry laboratory exercise  Jarret, Ronald M.; Sin, Ny
Molecular mechanics calculations can be used in conjunction with hand-held models for a more complete approach to the instruction of stereochemistry.
Jarret, Ronald M.; Sin, Ny J. Chem. Educ. 1990, 67, 153.
Stereochemistry |
Molecular Modeling |
Molecular Mechanics / Dynamics
Flow chart determination of isomeric relationships  Black, Kersey A.
This flow chart presentation is particularly effective in helping the student to distinguish between the different types of stereochemical relationships.
Black, Kersey A. J. Chem. Educ. 1990, 67, 141.
Stereochemistry
Van't Hoff, Le Bel, and the development of stereochemistry: A reassessment  Grossman, Robert B.
The author gives a review of and possible explanations for Van't Hoff's inconsistencies.
Grossman, Robert B. J. Chem. Educ. 1989, 66, 30.
Stereochemistry |
Group Theory / Symmetry
Stereochemistry of cyclic hydrocarbons   Perkins, Robert R.
The topic of stereochemistry always poses great difficulties for many students in introductory organic chemistry. The following problems can be used as a tutorial question after having introduced the various terms associated with stereochemistry. The question requires skills at the applications level in the Bloom taxonomy.
Perkins, Robert R. J. Chem. Educ. 1988, 65, 860.
Alkanes / Cycloalkanes |
Chirality / Optical Activity |
Stereochemistry |
Diastereomers |
Constitutional Isomers
Organic Stereochemistry, Review I (Bays, J. Philip)  Finzel, Rodney B.
Software intended to cover the concepts of stereochemistry as they are applied to organic molecules.
Finzel, Rodney B. J. Chem. Educ. 1987, 64, A116.
Stereochemistry |
Chirality / Optical Activity |
Enrichment / Review Materials
Molecular structure and chirality  Brand, David J.; Fisher, Jed
Clarification of the meaning of the term chiral and its application to both chiral and achiral molecules.
Brand, David J.; Fisher, Jed J. Chem. Educ. 1987, 64, 1035.
Molecular Properties / Structure |
Chirality / Optical Activity |
Stereochemistry |
Enantiomers
The nomenclature of relative stereochemistry: Choosing between likes and preferences  Brook, Michael A.
The commonly used descriptors for relative stereochemistry are introduced and compared.
Brook, Michael A. J. Chem. Educ. 1987, 64, 218.
Nomenclature / Units / Symbols |
Stereochemistry |
Molecular Properties / Structure |
Chirality / Optical Activity
A novel method for assigning R, S labels to enantiomers  Huheey, James E.
A procedure is suggested to provide students with greater insight into the properties of dissymmetrical molecules.
Huheey, James E. J. Chem. Educ. 1986, 63, 598.
Enantiomers |
Stereochemistry
Stress the twofold axis of the threo isomer  Tavernier, D.
The author weighs in on the the controversy of the threo and erythro nomenclature.
Tavernier, D. J. Chem. Educ. 1986, 63, 511.
Nomenclature / Units / Symbols |
Molecular Properties / Structure |
Stereochemistry |
Enantiomers |
Diastereomers
Determination of stereochemical relationships  Ayorinde, Folahan O.
A sequence of steps to enable students to arrive with relative ease at correct stereochemical relationships.
Ayorinde, Folahan O. J. Chem. Educ. 1985, 62, 297.
Stereochemistry |
Molecular Properties / Structure |
Chirality / Optical Activity |
Enantiomers |
Diastereomers
Models for illustrating chirality at two centers  Feldman, Martin R.
This note suggests common objects that can be used as models to illustrate chirality at two centers, and to introduce the concepts of diastereomers and the meso configuration.
Feldman, Martin R. J. Chem. Educ. 1984, 61, 1050.
Molecular Properties / Structure |
Molecular Modeling |
Chirality / Optical Activity |
Diastereomers |
Stereochemistry |
Enantiomers
Examples of diastereomers  Bell, William
Using right- and left-handed doors as examples of familiar objects that exhibit enantiomerism.
Bell, William J. Chem. Educ. 1984, 61, 901.
Stereochemistry |
Diastereomers |
Molecular Properties / Structure |
Chirality / Optical Activity
Diastereomers, geometric isomers, and rotation about bonds  McCullough, John J.
A simple and consistent introduction to the stereochemistry of carbon, diastereomers, and geometric isomers.
McCullough, John J. J. Chem. Educ. 1982, 59, 37.
Stereochemistry |
Diastereomers |
Molecular Properties / Structure
Stereochemistry and macromolecules: Principles and applications  Quirk, Roderic P.
This article was written to provide an introduction to the basic concepts of polymer stereochemistry and their applications.
Quirk, Roderic P. J. Chem. Educ. 1981, 58, 540.
Stereochemistry |
Chirality / Optical Activity |
Enantiomers
Glutamic acid in pheromone synthesis: A useful chiral synthon  Smith, Leverett R.; Williams, Howard J.
Outlines synthetic routes for the formation of various pheromones from glutamic acid.
Smith, Leverett R.; Williams, Howard J. J. Chem. Educ. 1979, 56, 696.
Synthesis |
Chirality / Optical Activity |
Natural Products |
Stereochemistry |
Enantiomers |
Amino Acids
Optical illusions in drawings of cyclohexane derivatives  Feldman, Martin R.
An optical illusion in the representation of chair cyclohexanes.
Feldman, Martin R. J. Chem. Educ. 1979, 56, 659.
Molecular Properties / Structure |
Stereochemistry |
Enantiomers |
Diastereomers |
Alkanes / Cycloalkanes
Selectivity and specificity in organic reactions  Ault, Addison
Distinguishes between various forms of selectivity and specificity (e.g. the us of and differences between stereoselective and stereospecific).
Ault, Addison J. Chem. Educ. 1977, 54, 614.
Reactions |
Stereochemistry |
Diastereomers |
Enantiomers |
Nomenclature / Units / Symbols
Synthesis of 4-methyl-3-heptanol and 4-methyl-3-heptanone. Two easily synthesized insect pheromones  Einterz, Robert M.; Ponder, Jay W.; Lenox, Ronald S.
A two step reaction sequence involving the Grignard synthesis of an alcohol followed by oxidation of this alcohol to the corresponding ketone.
Einterz, Robert M.; Ponder, Jay W.; Lenox, Ronald S. J. Chem. Educ. 1977, 54, 382.
Natural Products |
Synthesis |
Applications of Chemistry |
Grignard Reagents |
Mechanisms of Reactions |
Stereochemistry |
Alcohols |
Aldehydes / Ketones
Resolution and stereochemistry of asymmetric silicon, germanium, tin, and lead compounds  Belloli, Robert
It is the purpose of this review to summarize the results of stereochemical studies on compounds containing an asymmetric group IVA atom.
Belloli, Robert J. Chem. Educ. 1969, 46, 640.
Stereochemistry |
Organometallics |
Enantiomers |
Mechanisms of Reactions |
Nucleophilic Substitution