Many of us are have struggled with the problem of how to modify our organic laboratory curriculum to reduce the amount of waste generated and make the lab safer for our students. At the University of Oregon we have developed a new organic chemistry lab curriculum based upon the principles of “green” chemistry¹ to address these challenges. Here I will describe both the practical advantages of this curriculum and suggest that it provides outstanding opportunities to positively influence students' opinions about chemistry and encourage them to take an active part in shaping the future of chemistry in our society.

The traditional approaches to minimizing waste and improving safety in the organic lab involve microscale apparatus and increased ventilation. We initially pursued this approach, building a new laboratory where each student could perform his/her work with microscale glassware inside a fume hood. Although these changes reduced the amount of waste and provided a safer working environment, we were frustrated by two major disadvantages. A practical problem was that the lab's 18-student capacity meant night and weekend labs for some students. A more fundamental problem was that our reliance on microscale methods was not adequately preparing our students for working in our research labs or in industry.

In the process of addressing these issues we asked the question, “Can we use `green' chemistry methods to teach organic lab skills and chemical concepts using standard taper glassware on the benchtop?” Our goal was to use the latest advances in green chemistry research to develop a new lab curriculum that would decrease our reliance on fume hoods, produce a less hazardous wastestream, and make lab safer. The fact that green methods improve safety by eliminating hazards as opposed to preventing exposure through often-fallible safety controls/procedures made it ideal for implementing in a teaching lab. As we began to develop the idea, other benefits became evident: (a) green chemical methods achieve hazard reduction at all reaction scales, (b) incorporation of green methods is an excellent opportunity to upgrade the organic lab curriculum (that, with the exception of scale reduction, has remained virtually unchanged throughout the last century), and (c) the curriculum provides a unique context for more detailed discussion of chemical hazards and the effects of chemicals on human health and the environment.

We rapidly discovered there were few existing green experiments are available for the organic lab. Thus, we searched for existing experiments that could be modified to be greener and scanned for new reports of green methods that could be adapted to the teaching lab. We established criteria for judging the greenness of potential new experiments, including:

• Reduces laboratory waste and hazards
• Illustrates green chemical concepts
• Teaches modern reaction chemistry and techniques, in parallel with lecture course
• Provides a platform for discussion of environmental issues in the classroom
• Can be accomplished by students during a typical organic laboratory period
• Uses inexpensive, greener solvents and reagents
• Is adaptable to either macroscale or microscale methods

In cases where experiments were to be modified, we adopted a set of principles¹ to guide the process of modifying the experiments.

• Eliminate (minimize) hazardous solvents whenever possible – this includes both as reaction media and in solvent-dependent separations
• Identify and use the most benign reagents and solvents possible – in many cases traditional reagents are too reactive, so use milder, more selective reagents
• Develop and use efficient reaction chemistry – including catalysis, atom economy, etc.

Over the last two years we have student-tested the experiments we developed (based upon the above criteria) for Fall and Winter quarter labs. We have found that green organic laboratory is a practical mechanism for teaching core skills and concepts in a safer and environmentally-friendlier manner.

In the process of testing the curriculum, we discovered that there are a number of unexpected benefits. One such benefit is that students are regularly required to evaluate the chemical hazards associated with a method and learn to take appropriate precautions (as opposed to taking the stance that all chemicals are hazardous and should be avoided). They learn the types of chemical hazards and how those hazards are quantified, the relevant modes of exposure or release of chemicals, and the methods to be used for safe handling of chemicals with different hazards. By addressing chemical hazards in this way, students learn to assess hazard rather than thinking that all chemicals are “toxic”. This alters their (often) negative perception of chemistry.

Another significant benefit derives from students being exposed to the strategies and methods we used to make the experiments green. It would be possible to adopt a greener organic lab curriculum without involving students in the process, however, to do so is to miss a rare opportunity to change the way that students view chemistry and their perceived ability to contribute to it. For each experiment, we show the students how the new green method differs from the traditionally-used method and describe the thought process we or others used in modifying the experiment. This repeated exposure to the process of analyzing reaction conditions and finding alternative methods teaches students to: (a) assess the conditions for hazards and likelihood of exposure/release, (b) identify new methods that allow reduction of the hazards, (c) explore how alternative methods can affect the course and rate of reactions, and (d) assess the broader impact of the overall process on safety and the environment. This aspect of the curriculum is especially empowering to students. They realize that armed with this knowledge they can help disseminate better and more sustainable chemical practices throughout academic and industrial settings acting as ambassadors of green chemistry.

Although our green organic lab curriculum is still evolving, we are excited about its practical advantages and the unique opportunities it offers for promoting chemistry as a responsible science. By introducing state-of-the-art green chemical methods, objectively discussing chemical hazards and preparing students to help shape the future of chemical practices, we can demonstrate to students that chemistry can be used to solve, rather than cause, environmental problems. For more information on green chemistry, the UO green organic lab curriculum, or the team that developed this curriculum check out our webpage at: http://darkwing.uoregon.edu/~hutchlab/greenchem/.

1. "Green Chemistry; Theory and Practice" Paul T. Anastas and John C. Warner, Oxford University Press, 1998.

James E. Hutchison, Published in ACS Division of Chemical Education Newsletter, Fall 2000, p54-55.