A Practical Oxidation Experiment for Undergraduate Students: Bobbitt’s Salt as a “Green” Alternative

Abstract

Oxidation reactions are critical components of the synthetic toolbox taught to undergraduate students during introductory organic chemistry courses. However, the oxidation reactions discussed in the undergraduate curriculum are often outdated as many organic chemistry textbooks emphasize chromium-based oxidants that are no longer in regular use by practitioners, which may limit an instructor’s time to allocate to discussion of other oxidants. Further, laboratory courses have since either removed oxidation experiments or replaced them with oxidative processes not discussed in lectures, thus leading to a disconnect between the two learning settings. As part of an effort to bridge this divide and modernize the oxidation reactions discussed in our curricula, we have developed a new laboratory experiment that uses a commercially available oxoammonium salt (Bobbitt’s salt) to cleanly oxidize cinnamyl alcohol to cinnamaldehyde. In addition to being a safe, convenient, colorimetric, and “green oxidant” suitable for use in the undergraduate teaching laboratory, the hydride-transfer mechanism allows for overlap with key course concepts presented in both introductory and advanced lecture courses. The procedure is well-suited for small and large organic I, II, or advanced laboratory sections alike and can be completed within a standard 3–4 h laboratory period. Aside from exposing students to a modern green oxidation protocol, the experiment contains expanded opportunities for interpretation of 1H NMR, 13C NMR, and IR spectra. An optional addendum for advanced students involving Hammett correlations was also developed.

Recent advancements in the use of Bobbitt's salt and 4-acetamidoTEMPO

“…Given the growing and wideranging application of Bobbitt's salt (1) and ACT (2) across several fields, this feature article aims to highlight recent advancements in their use, mechanistic underpinnings, and application. Our contributions [4][5][6][7][8][9][10][11][12][13][14] in expanding the utility, accessibility, and understanding of these two oxidants over the past 10 years and continued exploration of these reagents will offer a first-hand perspective towards the past and current trajectory of these oxidants as they proliferate into several fields of chemistry.…”

Preparation of Aminals under Continuous Flow Conditions

“…Aminals are a class of compounds easily accessible from the condensation of aldehydes with secondary amines, which are two fundamental functional groups in the Organic Chemistry curriculum. − Despite aminals being known for decades, organic chemists have focused solely on their use as protection of aryl aldehydes prior to lithiation. − Recent innovative reports on the use of aminals have emerged, , and we described a method to prepare those compounds under mild conditions by using copper catalysts, thus paving the way for new methodologies employing aminals as key synthons …”

Exploring curriculum adoption of green and sustainable chemistry in undergraduate organic chemistry courses: results from a national survey in the United States

“…5 Thus, knowledge of green chemistry is essential not just for the students who will pursue research or industrial jobs in chemically related fields, but by all students because it can provide a platform for connecting the course concepts to solving, or at least thinking about, relevant concrete examples which they can then later apply in their own fields and personal lives. 6 The integration of green and sustainable chemistry into the organic curriculum has recently been reported through laboratory experiments, [7][8][9][10][11] course-based undergraduate research experiences (CUREs), 12 comics, 13 videos, 14 infographics, 15 and student-generated letters to representatives about scientific topics. 16 Additionally, several literature reviews describing the integration of green chemistry into the chemistry curriculum can be found elsewhere.…”