A solvent-free, nickel-catalyzed [2 + 2+2 + 2] cycloaddition of alkynes to synthesize substituted cyclooctatetraene (COT) derivatives has been developed. This mechanochemical approach takes advantage of the frictional energy created by reusable nickel pellets, which also act as the catalyst. In contrast to solution chemistry, the major products are cyclooctatetraene isomers rather than substituted benzenes.

Vials, balls, foils, and pellets used in high-speed ball mills can be catalysts by themselves.

Green chemistry and sustainability have garnered more awareness in the chemical industry in recent years, but green chemistry classes are still not commonplace for either the undergraduate or graduate student curriculum. Additionally, many departments are seeking avenues to reach greater numbers and types of learners through online courses. To address both needs, a small group of chemistry graduate students set out to design a 3-credit-hour upper-level online green chemistry course targeted at students most likely to apply green chemistry concepts in their future careers. The goals for the course included education in the basics of green chemistry (history, metrics, methodologies) along with opportunities to apply what they have learned and communicate it to a general audience. This process of developing modules and assessments for the discovery and application of green chemistry principles has enabled a supplementary education for the graduate students as well. Herein, the specific motivations of the graduate students to design the course, how green chemistry was presented to students in an online format, and how students responded to this type of class are provided.

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Mechanochemistry through high-speed ball milling has become an increasingly popular method for performing organic transformations. This newfound interest in high-speed ball milling is in part driven by the benefit of performing reactions in the absence of solvent. Mechanochemical reactions are often conducted in stainless-steel vials with stainless-steel balls. Since stainless steel is made of several readily oxidizable metals (Fe, Cr, and Ni), reduction reactions using water as a hydrogen source were explored using a temperature-controlled mixer mill. Mechanistic studies suggest that the reduction proceeds via a single electron transfer (SET) pathway, with iron and nickel being essential components for the reaction.