Spectroscopic Unknown Puzzles from Real Data─A More Authentic Pedagogical Approach with Epistemological Implications

We present example assessments featuring spectroscopic unknown puzzles, where the solution to the puzzle is the outcome of a known chemical reaction. These spectroscopic exercises engage students in a substantially more authentic manner than the conventional structure elucidation puzzles that are ubiquitous in organic chemistry instruction. Students use the same information available to practicing organic chemists, i.e., the chemicals added to the reaction vessel and information regarding the intended reaction outcome, to support their interpretation of GC-MS, IR, and NMR data. This centers the purpose of spectroscopy and spectrometry on understanding chemical phenomena, often chemical reactions, rather than on solving inauthentic unknown puzzles which are not connected to a chemical phenomenon. We anticipate that repeated use of spectroscopy and spectrometry in this manner will communicate to students why organic chemists highly value these techniques and how they are used to construct knowledge in organic chemistry.