The ACS Green Chemistry Institute® Pharmaceutical Roundtable has assembled an updated list of key research areas to highlight transformations and reaction media where more sustainable technologies would be most impactful.

Green chemistry" refers to the promotion of safe, sustainable, and waste-minimizing chemical processes.The proliferation of green chemistry metrics without any clear consensus on industry standards is a significant barrier to the adoption of green chemistry within the pharmaceutical industry. We propose the Green Aspiration Level TM (GAL) concept as a novel process performance metric that quantifies the environmental impact of producing a specific pharmaceutical agent while taking into account the complexity of the ideal synthetic process for producing the target molecule. Application of the GAL metric will make possible for the first time an assessment of relative greenness of a process, in terms of waste, versus industry standards for the production process of any pharmaceutical. Our recommendations also include a simple methodology for defining process starting points, which is an important aspect of standardizing measurement to ensure that Relative Process Greenness (RPG) comparisons are meaningful. We demonstrate our methodology using Pfizer's Viagra TM process as an example, and outline aspiration level opportunities for industry and government to dismantle green chemistry barriers. † Electronic supplementary information (ESI) available: E factor preference and analysis details of Pfizer's Viagra TM commercial process. SeeThis journal is