Retrosynthetic analysis is a topic that presents significant conceptual challenges to students. To enable a more active learning of introductory retrosynthesis, we implemented a flipped approach, delivered over a 4 year period, to a class size of between 18 and 29 biochemistry students per year. This provided more time for in-class peer group learning and discussion, encouraging student-centered learning; the stepwise delivery of material was designed to reduce cognitive load. We monitored course grades and assessed students' attitudes toward this course, finding a consistent motivation and enthusiasm for the flipped format, which appears well-suited to the problem-solving aspects of retrosynthetic analysis. By sharing our motivations, strategies, course materials, and outcomes, we hope that this will inspire others to develop their own courses.