A series of experiments for undergraduate laboratory courses (e.g., inorganic, organometallic or advanced organic) have been developed. These experiments focus on understanding the design and catalytic activity of ruthenium–indenylidene complexes for olefin metathesis. Included in the experiments are the syntheses of two ruthenium–indenylidene complexes that can be conveniently prepared from commercially available starting materials. The two complexes differ only by the nature of the phosphine ligand, yet each complex displays drastically different catalytic activity in a ring-closing metathesis (RCM) reaction. When the triphenylphosphine-containing complex is utilized, little or no catalytic activity is observed. Substitution of the complex with tricyclohexylphosphine, however, results in a complex with excellent catalytic activity in a RCM reaction. These experiments demonstrate the importance of catalyst design and expose students to the important field of olefin metathesis. Students also utilize several analytical methods (1H and 31P NMR, GC–MS, FT-IR) in characterizing the complexes and quantifying catalytic activity.

This work provides insights on waterpipe tobacco and waterpipe charcoal as potential sources of environmental toxicants. Selected harmful and potentially harmful constituents (HPHCs) from ten U.S. commercial waterpipe tobacco filler products (before and after electric heating) and five waterpipe charcoal products (before and after burning) were investigated. The differences in quantities of HPHCs between the evaluated products appear to be affected by raw material properties and/or the manufacturing processes involved in product production. Trace metal quantities in waterpipe tobacco and charcoal products were observed after heating or burning conditions compared to unheated or unburned conditions, which could impact the environment through the generation of toxic tobacco product waste. This study demonstrates that waterpipe tobacco and waterpipe charcoal contain substantial quantities of benzo[a]pyrene (B[a]P) and trace metals ( i.e ., selenium, arsenic, cadmium, chromium, cobalt, lead, nickel) before use and that extensive and varied changes in trace metal quantities take place as a result of heating, and more studies are needed to estimate the magnitude of the environmental impact of waterpipe tobacco use.

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