A research-based inorganic chemistry laboratory course is described. Using the defined protocol of a course-based undergraduate research experience (CURE), students undertake a self-designed research project to identify new catalysts for the dehydrogenation of ammonia borane. Students select ligands and metals, prepare and characterize catalysts precursors, develop protocols for catalysts, and screen catalyst precursors. These activities are designed to align with the five components of a CURE (research activities, discovery, relevance, collaboration, and iteration), and this course is presented as one model from which individuals can develop CUREs at their own institutions. The students were assessed with the CURE survey, which showed gains in both research activities and understanding the nature of science.

Two cobalt compounds, Cp*Co(CO)I2 (1) and CpCo(CO)I2 (2) (Cp* = η(5)-C5Me5, Cp = η(5)-C5H5), catalyze the dehydrogenation of ammonia borane under either anaerobic or aerobic conditions and are also effective hydrogenation catalysts for alkenes and alkynes using ammonia borane as a hydrogen source, also in the presence of air.

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The thorium and uranium dihydride dimer complexes [(C5Me5)2An(H)(μ-H)]2 (An = Th, U) have been easily prepared using phenylsilane, which is an efficient and safer alternative to hydrogen gas. The synthetic utility of this new hydriding method has been demonstrated by the preparation of a variety of organometallic complexes, including, for the first time, (C5Me5)2U(SMe)2, (C5Me5)2Th(C4Ph4), (C5Me5)2U(C4Ph4), (C5Me5)2ThS5, and (C5Me5)2U(bipy) using [(C5Me5)2An(H)(μ-H)]2 (An = Th, U) as multi-electron reductants.

A commercially available iron compound, [CpFe(CO)] (1) (Cp = η-CH), is an efficient catalyst for the double hydrophosphination of terminal aryl alkynes with diphenylphosphine under visible light irradiation or thermal conditions with a reduction of reaction times of up to two orders of magnitude for some substrates over literature reports. The 1,2-bis(diphenylphosphino)ethane products generated in these reactions are readily isolated in high yields.

[CpFe­(CO)2]2 (1) (Cp = η5-C5H5) is an effective precatalyst for the hydrophosphination of alkenes with Ph2PH under visible light irradiation, which appears to be a unique way to promote metal-catalyzed hydrophosphination. Additionally, 1 is a photocatalyst for the dehydrogenation of amine boranes and formation of siloxanes from tertiary silanes. These reactions have similar, if not improved, reactivity over the same transformations using 1 or related CpFeMe­(CO)2 under UV irradiation, consistent with the notion that hydrophosphination with 1 proceeds via formation of CpFe­(CO)2 •. These results demonstrate that catalyst selection can avail the use of commercially available LED bulbs as photon sources, potentially replacing mercury arc lamps or other energy intensive processes in known or new catalytic reactions.

This work demonstrates that the oxidation state and chemistry of uranium hydrides can be tuned with temperature and the stoichiometry of phenylsilane. The trivalent uranium hydride [(C 5 Me 5 ) 2 U−H] x (5) was found to be comprised of an equilibrium mixture of U(III) hydrides in solution at ambient temperature. A single U(III) species can be selectively prepared by treating (C 5 Me 5 ) 2 UMe 2 (4) with 2 equiv of phenylsilane at 50 °C. The U(III) system is a potent reducing agent and displayed chemistry distinct from the U(IV) system [(C 5 Me 5 ) 2 U(H)(μ-H)] 2 (2), which was harnessed to prepare a variety of organometallic complexes, including (C 5 Me 5 ) 2 U(dmpe)(H) (6), and the novel uranium(IV) metallacyclopentadiene complex (C 5 Me 5 ) 2 U(C 4 Me 4 ) (11).

A general, atom-economical method for the synthesis of phosphaalkenes is reported via the net coupling of primary alkyl or aryl phosphines with aryl or alkyl isocyanides at zirconium. The phosphorus-containing ligand can be liberated as the phosphaformamide from zirconium by reaction with an organic electrophile.