The hydrolysis of esters and difunctional ethers catalyzed by Cp′ 2 Mo(OH)(H 2 O) + (1) (Cp′ ) η 5 -C 5 H 4 CH 3 ) and the stoichiometric oxidation of CO to CO 2 in the presence of 1 are described. These reactions, combined with the previously reported nitrile hydrations and phosphate esters hydrolyses catalyzed by 1, demonstrate that 1 is an effective homogeneous catalyst for hydration, hydrolysis, and oxidation reactions in aqueous solution under mild conditions (pH ∼7, ∼80 °C). Each reaction is proposed to proceed by intramolecular attack of the hydroxide ligand on a bound substrate. The intramolecular nature of the reaction is supported by the ester hydrolysis activation parameters (∆H q ) 5.9 ( 0.7 kcal/mol and ∆S q ) -48 ( 9 eu), the lack of H/D exchange, and the significant increase (10 6 -10 8 ) in the rate of hydrolysis over uncatalyzed hydrolysis.

Cp′ 2 Mo(µ-OH) 2 MoCp′ 2 ] 2+ (1) (Cp′ ) η 5 -CH 3 C 5 H 4 ) is a precatalyst for the hydration of nitriles in aqueous solution under mild conditions (∼80 °C). Among the nitriles hydrated were acetonitrile, isobutyronitrile, benzonitrile, 3-hydroxypropionitrile, 3-bromopropioamide, 4-cyanopyridine, succinonitrile, methyl cyanoacetate, 2-methoxyacetonitrile, and acrylonitrile. Except in the case of 2-methoxyacetonitrile, hydrolysis of the resulting amide products did not occur. Hydration of the CdC double bond did not occur in acrylonitrile, but hydrolysis of ester and ether linkages did occur in nitriles containing those functional groups. The apparent rate constants and turnover frequencies of the catalytic reactions were determined using an iterative kinetics-fitting program. The rates and turnover frequencies are comparable to those reported for many homogeneous nitrile hydration catalysts described in the literature. In aqueous solution, 1 is in equilibrium with [Cp′ 2 Mo(OH)(H 2 O)] + (2), and this monomer is proposed to be the active hydration catalyst. The hydration is proposed to occur by an intramolecular attack of a hydroxide ligand on a coordinated nitrile. The hydration reaction is irreversibly inhibited by product and reversibly inhibited by substrate (nitrile).

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The COVID-19 pandemic resulted in the mass shutdown of universities across the United States in the spring of 2020. As the pandemic progressed, regional regulations resulted in a broad range of teaching modalities for the 2020–2021 academic year. While some regions remained tightly locked down (resulting in online-only instruction), others allowed limited or full campus operations within higher education. Located in Spokane, WA, Whitworth University is a small, liberal arts university which was allowed limited operations under a socially distanced model. While the pandemic resulted in some obvious campus changes (for example, masks were required on campus), more subtle changes were required at the curricular level. Adopting a flex model where students and faculty were allowed the option to participate online only while in-person classes were offered, Whitworth maintained in-person education through the 2020–2021 academic year. This FLEX model presented specific difficulties to laboratory courses due to social distancing restrictions. In this work, we describe five models developed in the Whitworth University Department of Chemistry toward teaching laboratories in a socially distanced manner with reduced room capacity. The primary modes of instruction were (1) a reduction of in-person laboratory time so that only half of the students were working in the laboratory at any given time, (2) an alternating weeks model where students came to the laboratory every other week and performed online laboratory experiences in the off weeks, (3) a split room model where one faculty member oversaw two laboratory spaces containing one-half of the normal number of students, (4) a higher number of smaller lab sections where social distancing could be maintained, and (5) a hybrid technique utilizing several of these concepts dependent upon the learning outcomes of the laboratory procedure each week. Benefits and challenges for each model are described by faculty herein. End-of-semester student course evaluation scores provide a comparison of student perceptions of learning outcomes and experiences in the laboratory in the various models. In addition, grade point averages were compared to prior years. Finally, departmental leadership provides insight on the administrative challenges of implementing these course models. Statistically, the models presented no significant change in student perceptions of learning or grade point averages for most courses regardless of the model when compared to prior offerings of these courses. Overall, the implementation of these protocols allowed students hands-on laboratory experiences with a minimal impact on the curriculum presented.