1-Bromobutane Lab Report
Laboratory Experiment pubs.acs.org/jchemeduc NMR Kinetics of the SN2 Reaction between BuBr and I−: An
Introductory Organic Chemistry Laboratory Exercise
T. Andrew Mobley*
Department of Chemistry, Grinnell College, Grinnell, Iowa 50112, United States
S Supporting Information
*
ABSTRACT: A simple organic chemistry experiment is described that investigates the kinetics of the reaction between 1-bromobutane (BuBr) and iodide (I−) as followed by observing the disappearance of BuBr and the appearance of 1-iodobutane (BuI) using 1H NMR spectroscopy. In small groups of three to four, students acquire data to examine the concentrationdependence of both the organic substrate and the nucleophile under pseudofirst-order and second-order conditions. After …show more content…
Students discuss the experimentally determined rate law, comparing it to that predicted for this SN2 reaction.
KEYWORDS: Second-Year Undergraduate, Hands-On Learning/Manipulatives, Laboratory Instruction, Organic Chemistry,
Physical Chemistry, Kinetics, Rate Law, Mechanisms of Reactions, Nucleophilic Substitution, NMR Spectroscopy or the last 10 years, an introduction to kinetics in the first term of second-year undergraduate organic chemistry has been taught with the experiment described herein; approximately 1000 students have completed the experiment.1 The introductory organic chemistry course serves as an ideal setting for teaching kinetic theory, with this experiment coming twothirds of the way through the first semester of a two-semester organic sequence. At this point, our students have a firm basis in structural concepts, are able to translate simple NMR spectra into chemical structures, and understand the concept of a reaction mechanism. Concurrent with this experiment, students are learning in the classroom the fundamentals of reaction kinetics and the mechanisms of bimolecular and …show more content…
Similarly, many laboratory assistants have been of great assistance in leading students through the processing portion of the experiment. Thanks are also in order for Gretchen
Hofmeister who assisted in translating Bruker instructions to
Varian and Daniel O’Leary who checked the Bruker instructions provided in Supporting Information. Of course, the students who acquired, processed and analyzed the data over the past decade deserve the greatest acknowledgement.
■
REFERENCES
(1) Mobley, T. A.; Trujillo, H. A.; Lindberg, J. G. NMR Kinetics of the SN2 Mechanism of the Finkelstein Reaction: Teaching Kinetics in the Organic Laboratory. In Abstracts of Papers, 225th ACS National
Meeting, New Orleans, LA, March 23−27, 2003; American Chemical
Society: Washington, DC, 2003; CHED-1277.
(2) Swearingen, L.; Florence, R. T. The Solubility of Sodium
Bromide in Acetone. J. Phys. Chem. 1934, 39 (5),
Introductory Organic Chemistry Laboratory Exercise
T. Andrew Mobley*
Department of Chemistry, Grinnell College, Grinnell, Iowa 50112, United States
S Supporting Information
*
ABSTRACT: A simple organic chemistry experiment is described that investigates the kinetics of the reaction between 1-bromobutane (BuBr) and iodide (I−) as followed by observing the disappearance of BuBr and the appearance of 1-iodobutane (BuI) using 1H NMR spectroscopy. In small groups of three to four, students acquire data to examine the concentrationdependence of both the organic substrate and the nucleophile under pseudofirst-order and second-order conditions. After …show more content…
Students discuss the experimentally determined rate law, comparing it to that predicted for this SN2 reaction.
KEYWORDS: Second-Year Undergraduate, Hands-On Learning/Manipulatives, Laboratory Instruction, Organic Chemistry,
Physical Chemistry, Kinetics, Rate Law, Mechanisms of Reactions, Nucleophilic Substitution, NMR Spectroscopy or the last 10 years, an introduction to kinetics in the first term of second-year undergraduate organic chemistry has been taught with the experiment described herein; approximately 1000 students have completed the experiment.1 The introductory organic chemistry course serves as an ideal setting for teaching kinetic theory, with this experiment coming twothirds of the way through the first semester of a two-semester organic sequence. At this point, our students have a firm basis in structural concepts, are able to translate simple NMR spectra into chemical structures, and understand the concept of a reaction mechanism. Concurrent with this experiment, students are learning in the classroom the fundamentals of reaction kinetics and the mechanisms of bimolecular and …show more content…
Similarly, many laboratory assistants have been of great assistance in leading students through the processing portion of the experiment. Thanks are also in order for Gretchen
Hofmeister who assisted in translating Bruker instructions to
Varian and Daniel O’Leary who checked the Bruker instructions provided in Supporting Information. Of course, the students who acquired, processed and analyzed the data over the past decade deserve the greatest acknowledgement.
■
REFERENCES
(1) Mobley, T. A.; Trujillo, H. A.; Lindberg, J. G. NMR Kinetics of the SN2 Mechanism of the Finkelstein Reaction: Teaching Kinetics in the Organic Laboratory. In Abstracts of Papers, 225th ACS National
Meeting, New Orleans, LA, March 23−27, 2003; American Chemical
Society: Washington, DC, 2003; CHED-1277.
(2) Swearingen, L.; Florence, R. T. The Solubility of Sodium
Bromide in Acetone. J. Phys. Chem. 1934, 39 (5),