Choosing the Greenest Synthesis: A Multivariate Metric Green Chemistry Exercise

The ability to correctly identify the greenest of several syntheses is a particularly useful asset for young chemists in the growing green economy. The famous univariate metrics atom economy and environmental factor provide insufficient information to allow for a proper selection of a green process. Multivariate metrics, such as those used in life-cycle assessment (LCA) to determine environmental impact, are much more informative. A team exercise was developed, based upon nine LCA environmental impact metrics, where students are tasked with selecting the greenest synthesis from a set of literature procedures. Students select the greenest synthesis by quantifying the environmental impact of all the materials involved in each synthesis rather than solely the quantity of generic waste produced, as occurs with univariate metrics.