As possible substrates for one-photon infrared-pumped reaction (IRPR), the structures and decomposition paths of complexes between AlH4 - and three proton donors, H2O, HF, and HCl, have been studied by ab initio methods. In each case only one transition state was found for the proton-transfer and H2-loss process. For each cluster, the geometry and energy characteristics of reactants, complex, transition state, and products were analyzed with [AlH4···HCl]- emerging as the best IRPR candidate. The MP2//6-311++G**-calculated intrinsic reaction coordinate (IRC) confirmed the one-step proton transfer and H2 loss with no intermediate. Classical trajectories were calculated on the ab initio potential-energy surface, beginning from a large number of initial conditions. With zero-point vibrational energies (ZPVE = 1/2hνi) assigned to all normal modes, based on their calculated harmonic frequencies, νi, one or more additional excitation quanta were added to modes associated with Cl−H and Al−H stretching. Proton transfer from HCl and loss of H2 were calculated to occur on the femtosecond time scale when stretching modes involving the dihydrogen-bonded hydrogens were excited. However, many vibrational oscillations take place before H2 release. Analysis of the dynamics in terms of the complex's normal modes indicates that the excitation in the reaction-relevant modes remains localized on a time scale >1 ps.

University of MichiganDearborn offers a one semester, two credit, stand-alone Organic Chemistry Laboratory course aimed at students with an interest in health-related careers. The COVID-19 pandemic led to a campus closure and a subsequent transition to a partially remote laboratory curriculum developed on-the-fly for the Winter 2020 semester followed by a full online course for our summer, accelerated sessions. The online structure is a hybrid of readings, student made videos, instructor demonstrations, laboratory simulations, and structure elucidation assignments. From our first iteration of the fully remote laboratory course, students are able to learn technique concepts and reaction background, interpret characterization data at similar levels to the face-to-face instruction setting. However, since the experimental execution is visualized or simulated, it is more challenging to assess the skills’ gained.

The main thickening agent or soap in multipurpose grease, lithium 12hydroxystearate, is a chemical commodity for the auto industry. This compound is obtained from castor oil via a series of chemical transformations. The first step, hydrogenation of castor oil, has been developed into a laboratory experiment for second-year undergraduate organic chemistry. Students are introduced to catalytic transfer hydrogenation (CTH) as a method to reduce a carbon−carbon double bond in ricinoleic acid, the main fatty acid in castor oil. Students perform a comparative analysis based on calculation of several green metrics: atom economy, E factor, reaction mass efficiency, CO 2 emissions, and costs. The product, hydrogenated castor oil, is characterized by several techniques: 1 H NMR and IR spectroscopy, and melting point.

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An upper-division laboratory project has been developed as a collaborative investigation of a reaction routinely taught in organic chemistry courses: the reduction of carbonyl compounds by borohydride reagents. Determination of several trends regarding structure−activity relationship was possible because each student contributed his or her results to an overall data set in a situation similar to a research environment. The students learned to use 1 H NMR techniques for in situ kinetic determinations and collaborated with classmates to develop a complete theory for structure−activity effects in the kinetics of this fundamental organic reaction.