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The COVID-19 pandemic put an abrupt end to face-to-face teaching at many colleges and universities. While numerous methods for synchronous and asynchronous teaching in lecture courses were quickly deployed, laboratory instruction presented a unique set of challenges. To develop online laboratories quickly would be a daunting task for an individual. However, contributions of many individuals could ease and hasten the transition to using virtual laboratories. The IONiC-VIPEr community of practice is one such community that sprung to action to provide virtual alternatives for inorganic chemistry laboratory instruction.

ACS Examinations provide a lens through which to examine historical changes in topic coverage via analyses of course-specific examinations. This study is an extension of work completed previously by the ACS Exams Research Staff and collaborators in general chemistry, organic chemistry, and physical chemistry to explore content changes in the principal courses of the postsecondary chemistry curriculum. In this study, we consider how inorganic chemistry content coverage has varied over a 55-year period since the first inorganic chemistry ACS Examination was released in 1961. A total of 860 items was evaluated on the basis of problem type (i.e., algorithmic, conceptual, or recall), use of visual-spatial or reference components, and content coverage. Our analyses identify core content areas in the inorganic chemistry curriculum, consistent with those reported in faculty surveys. Each examination also contained questions addressing a variety of specialty areas that vary widely within the discipline between 1961 and 2016. Unlike the results from historical reviews of general chemistry and organic chemistry ACS Examinations, we observe great variability across the 13 inorganic chemistry examinations with an absence of strong trends in inclusion or exclusion of problem types, visual-spatial or reference components, or content across the 13 exams analyzed. Our results offer a framework for using historical ACS Examinations as a tool to make decisions about the future of content coverage in postsecondary inorganic chemistry education.

The addition of Na[BArF24] (BArF24 = tetrakis(3,5-bis(trifluoromethyl)phenyl)borate) to [Pd(PP)Cl2] (PP = 1,1′-bis(phosphino)ferrocene ligands) compounds results in the loss of a chloride ligand and the formation of the dimeric species [Pd2(PP)2(μ-Cl)2][BArF24]2. In most cases, the addition of a monodentate phosphine, PR3, to these dimeric species leads to cleaving of the dimer and formation of [Pd(PP)(PR3)Cl][BArF24]. While these reactions are readily observed via a significant color change, the 31P{1H} NMR spectra offer more significant support, as the singlet for the dimer is replaced with three doublets of doublets. The reaction seems to take place for a wide range of PR3 ligands, although there do appear to be steric limitations to the reaction. The compounds were thoroughly characterized by NMR, and X-ray crystal structures of several of the compounds were obtained. In addition, the ferrocenyl backbone of the 1,1′-bis(phosphino)ferrocene ligands provides an opportunity to examine the oxidative electrochemistry of these compounds. In general, the potential at which oxidations of these compounds occurs shows a dependence on the phosphine substituents. [ABSTRACT FROM AUTHOR]

The catalytic activity of a series of [(AuCl)2(μ-PP)] (PP = 1,1′-bis(phosphino)metallocene ligands) compounds in the presence of Na[BArF24] (BArF24 = tetrakis(3,5-bis(trifluoromethyl)phenyl borate)) was examined in the formation of disubstituted furans from pyridine-N-oxide and terminal alkynes. The products of these reactions were typically the 2,5-disubstituted furans, but in the case of using 2-ethynylpyridene, the 2,4-disubstituted furan formed. The catalytic efficiency was dependent upon both the nature of the terminal alkyne and the 1,1′-bis(phosphino)metallocene ligands. During the course of this study, two new compounds, [(AuCl)2(μ-dppr)] and [(AuCl)2(μ-dppo)] (dppr = 1,1′-bis(diphenylphosphino)ruthenocene; dppo = 1,1′-bis(diphenylphosphino)osmocene), were prepared and characterized by NMR. X-ray crystal structures of both compounds were determined and the oxidative electrochemistry of these new compounds was examined. [ABSTRACT FROM AUTHOR]

An experiment to prepare a deuterium labeled adduct of a Lewis acid and Lewis base, to use computational methods allowing students to visualize the LUMO of Lewis acids, the HOMO of Lewis bases and the molecular orbitals of the adduct that is formed is developed. This allows students to see the interplay between calculated and experimental results.

The Ru-Ru bond is the site of the protonation of the unsymmetrical, monophosphine complexes Cp(PR3)Ru(mu-CO)2Ru(CO)Cp with CF3SO3H, rather than at the more basic Ru which bears the more strongly donating PR3 ligand. This was gleaned from 1H, 13C and 31P nuclear magnetic resonance and X-ray diffraction studies. The protonation of Cp2Ru2(CO)3(PR3) and Cp2Mo2(CO)4(PR3)2 with CF3SO3H is also discussed.

Research was conducted to examine the cyanide ligand basicities in Cp'M(L)2CN complexes (M = Ru, Fe). A wide range of Cp'M(L)2CN complexes were used which provided a chance to investigate the correlations among delta-H(sub CNH), nu-CN and 31P NMR chemical shifts and other ligand paramaters. Results indicate that the basicities (-delta-H(sub CNH)) of the CpRu(PR3)2CN complexes increased as the donor abilities of the phosphines (-delta-H(sub HP)) increased.

Basicities of metal within mononuclear organometallic compounds act as indictors of other reactivities. The basicities of the metal-metal bonds in a set of Cp'sub2Rusub2(CO)sub4 compounds containing several cyclopentadienyl-type ligands, are reported, using titration calorimetry. They are defined as the enthalpies of protonation (DeltaHMHM) of metal compounds with triflic acid (CFsub3SOsub3H) with 1,2-dichlorethane solution.