Comparing the Traditional with the Modern: A Greener, Solvent-Free Dihydropyrimidone Synthesis
Evangelos Aktoudianakis, Elton Chan, Amanda R. Edward, Isabel Jarosz, Vicki Lee, Leo Mui, Sonya S. Thatipamala, and Andrew P. Dicks
Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada
A microscale organic synthesis experiment is outlined where students undertake both a "traditional" and "modern" Biginelli preparation of a dihydropyrimidone, within the same three-hour session. Each method is straightforward, appropriate as part of a mid-level undergraduate laboratory, and performed individually or between a pair of students. Emphasis is placed on comparing approaches from a green chemistry perspective. The class probes concepts of catalytic reactivity, solvent-free synthesis, atom economy, and energy consumption to assess green improvements made by employing the modern strategy.
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