Comparing the Traditional with the Modern: A Greener, Solvent-Free Dihydropyrimidone Synthesis

Abstract

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.

Greening the organic chemistry laboratory: a comparison of microwave-assisted and classical nucleophilic aromatic substitution reactions

“…The UN World Decade of an Education for Sustainable Development ended in 2014, and in that time, a curricular revolution has been realized where green chemistry content has become imbedded into undergraduate chemistry (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16). Future chemists will decide whether chemistry will develop with sustainability as part of the focus, but only if they have a strong foundation on sustainability issues and the meaning of making green chemistry development decisions.…”

The E Factor and Process Mass Intensity

“…In another study, Aktoudianakis et al compared a traditional synthesis with a modern solvent-free approach in the context of the Biginelli reaction (Scheme 3.4) [14]. This multicomponent reaction has an E mw of 0.14 (88 % atom economy) and is ideal in an undergraduate laboratory setting, as the solvent-free reaction is completed within 15 min.…”

Beyond problem-based learning: using dynamic PBL in chemistry

“…Sustainable development is defined as ''development that meets the needs of the present without compromising the ability of future generations to meet their own needs'' (UN, 1992). Much of the focus in the implementation of green chemistry in the curricula has been on more effective and efficient organic synthesis (Andraos, 2012), the replacement of solvents (Aktoudianakis et al, 2009) or catalysis (Clarke et al, 2012;Dicks and Batey, 2013). The principles of green chemistry are well established (Anastas, 2011) and the twelve principles of green chemistry were published nearly 20 years ago (Anastas and Warner, 1998).…”