Kinetic Study of the Heck Reaction: An Interdisciplinary Experiment

Abstract

The aim of this experiment is to study and calculate the kinetic constant of a Heck reaction: the arylation of but-3-en-2-ol by iodobenzene catalyzed by palladium acetate in presence of triethylamine in DMF. The reaction leads to a mixture of two ketones. Students use GC analysis to quantify reagents and products of reaction. They control the global order of the reaction and prove that the two products are formed by two reactions that are in parallel. Finally, they calculate the rate constant for each reaction. Students calculate iodobenzene conversion, each product selectivity, yield, and catalyst turn over number (TON). These calculations are controlled using an internal standard, (-)-fenchone. This experiment is completed by students during their second-year kinetic laboratory and is done in pairs in a four-hour laboratory. This work allows students to work in the fields of organic and analytical chemistry, catalysis, and kinetics at the same time.

Green Oxidative Homocoupling of 1-Methylimidazole

“…Some previous versions of this transformation used stoichoiometric quantities of copper- or nickel-containing compounds, so the use of a catalytic amount of copper is an improvement in the greenness and elegance of the reaction. A growing number of lab experiments incorporate green chemistry. − , An introduction to green chemistry was given in the student handout for the experiment.…”

“…The teaching laboratory offers an opportunity to cover this subject matter. Indeed, a few pedagogical experiments relate to this topic; − however, most of these examples focus on palladium- or ruthenium-catalyzed reactions.…”

Comparing Industrial Amination Reactions in a Combined Class and Laboratory Green Chemistry Assignment

“…Experimental data from the B–H synthesis are collected and averaged to afford the results given to students (mean amounts of reagents used and mean product yield). Although there are multiple examples of palladium-catalyzed reaction procedures in the educational literature, − to our knowledge this represents the first example of a B–H reaction adapted for a pedagogical laboratory experiment.…”

Green Reductive Homocoupling of Bromobenzene

“…Because previous versions of this transformation used catalytic or even stoichoiometric quantities of copper- or nickel-containing compounds, , the reaction described here is significantly greener because iron compounds are more benign. A growing number of laboratory experiments incorporate green chemistry. − , An introduction to green chemistry was given in the student handout for the experiment (see the Supporting Information). One aspect of the reaction that students can analyze is how it could be made greener…”

“…The associated teaching laboratory offers an opportunity to discuss complementary subject matter. A few pedagogical experiments are available to introduce the topic; − most of these focus on palladium- or ruthenium-catalyzed reactions.…”