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This account reviews published green chemistry teaching resources in print and online literature and our experiences in teaching the subject to undergraduate students. Effective practices in lecture and laboratory are highlighted and ongoing challenges are addressed, including areas in cutting edge green chemistry research that impact its teaching in the undergraduate curriculum. In particular, the influence of green chemistry on the overall teaching of organic chemistry is discussed. Challenges in teaching green chemistry 1. Examples across the chemical sub-disciplinesMost literature examples of green chemistry in the context of optimized syntheses are from an organic perspective. This includes pharmaceutically important target molecules such as sildenafil citrate (Viagrat) (Dunn et al., 2004;Dicks and Batey, 2012;Edward, 2012) and ibuprofen (Advilt) (Cann and Connelly, 2000). As such, the vast majority of green

Irradiation of 2-azidofluorene in an aqueous solution containing 2‘-deoxyguanosine (dG) gives good yields of 8-(2-fluorenylamino)dG. This is the C8 adduct implicated in the carcinogenicity of 2-aminofluorene, and formed in vivo from the reaction of DNA-guanine and an ester of N-hydroxy-2-aminofluorene. Flash photolysis of the azide reveals two intermediates on the pathway that forms this adduct, the 2-fluorenylnitrenium ion, and a subsequent longer-lived species formed in the reaction of this ion with dG. A number of pieces of evidence identify this later intermediate as the initial C8 adduct derived from addition of the nitrenium ion to the C8 carbon prior to loss of the C8 proton. Both spectroscopic and kinetic analyses show that the latter actually exists in both a cationic acid form and a base form, with a pK a for the acid of 3.9. The base form is a tautomer of the final product and is the species present at pH 7. There is also evidence that the reaction of the nitrenium ion and dG that forms this intermediate proceeds directly by addition at C8. In other words, the substitution of ArNH+ for H+ at the C8 position of 2‘-deoxyguanosine is a straightforward electrophilic aromatic substitution.

These results show clearly that amino-acid- and protein-bound Cu2+ can be reduced by thiolate ion to Cu+, which will generate NO from RSNO species, thus providing a realistic model for these reactions in vivo.

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This article describes the successful implementation of an oral examination format in the organic chemistry curriculum at the University of Toronto. Oral examinations are used to replace traditional written midterm examinations in several courses. In an introductory organic class, each student is allotted 15 min to individually discuss one pre-selected "named" reaction with the course instructors. To stimulate further learning, students must choose a particular reaction that has not been presented during lecture or performed in the laboratory. In upper-level courses, students review selected literature syntheses of either a drug molecule or natural product. The oral examination format provides a dynamic assessment approach that can be individualized to facilitate an in-depth analysis of student comprehension.

Used cooking oil disposal is a concern at the global scale. Direct disposal from domestic households and restaurants via drains can result in serious environmental issues. In this study, waste cooking oil was collected directly from vats in a McDonald’s restaurant and acrylated via a straightforward one-step reaction. After the addition of a photoinitiator and without any photoinhibitor, the product can be printed using a commercial 3D printer. The formulated resin produced high-resolution prints with features down to 100 micrometers. The rapid prototyped prints show considerable thermomechanical stability, morphological homogeneity, and biodegradability when compared to a state-of-the-art research resin and a commercial resin. This paper introduces the concept that waste cooking oil can be directly converted into a high-value commercial 3D-printing resin, which may have considerable societal benefits including reduction of waste and carbon emissions.

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