The hypothetical assertion that there are potentially millions of ionic liquids (ILs) can be validated using basic knowledge of IL precursors and simple calculations. While it is an interesting thought exercise to ponder the possibilities of ILs, it is important to investigate how many discrete ILs (i.e., unique cation and anion pairings) have actually been synthesized and reported in the literature. A complete analysis of all ILs is a daunting task, especially if the definition of what constitutes an IL is broad. Nonetheless, insight can be gained into the use of ILs over the past ∼20 years from a focused analysis of systematically varied 1,3dialkylimidazolium-based ILs (i.e., [R 1 R 2 im][X], where R 1 and R 2 are n-alkyl chains and X is either a halide or molecular anion). This family of ILs includes many of the most widely used and most thoroughly studied IL substances, including 1-butyl-3-methylimidazolium hexafluorophosphate ([C 4 mim][PF 6 ]) and 1-ethyl-3-methylimidazolium bistriflimide ([C 2 mim][Tf 2 N]). Using data retrieved from SciFinder searches, we analyzed the variety and frequency of 1,3-dialkylimidazolium-based ILs appearing in the literature. Our analysis reveals that there is a relatively large number of simple 1,3-dialkylimidazolium cations which have not yet been synthesized. Our findings indicate that despite the broad possibilities of IL structures available, there are but a handful of ILs that are commonly used and studied. Within the 1248 [R 1 R 2 im][X] ILs studied, there were only 12 cations extensively used, which included [R 1 R 2 im] + (R 1 = C 1 and R 2 = C 1 −C 12 ). Of the 16 anions studied, only 5, including [BF 4 ] − , [Cl] − , [PF 6 ] − , [Tf 2 N] − , and [Br] − , were used significantly. Thus, it appears that although ILs can be used as designer solvents with task-specific properties, there is a small default subset of ILs, which are "go-to" or "one-size-fits-all." We rationalize the current state of the IL landscape in terms of the historical perceptions (and misconceptions) around ILs, familiarity, availability and cost of starting materials, commercial availability of ILs, and the motivations from which researchers choose to synthesize and characterize new ILs.

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1-Vinylimidazole has been extensively utilized by the polymer science community, due to its high reactivity for free radical polymerization and the variety of uses for both neutral polyvinylimidazole and cationic polyvinylimidazolium forms. While much rarer, 4-vinylimidazoles and 2-vinylimidazoles are less synthetically accessible. In comparison to conventional methods for the synthesis of vinylimidazole derivatives from energy-intensive reaction conditions utilizing hazardous, gaseous precursors, herein we demonstrate a simple and versatile two-step method applied to the synthesis of seven 1-vinylimidazoles with different substituents as well as an initial demonstration of a facile method to synthesize the rare compound 1-methyl-2-vinylimidazole. The process relies upon the synthesis of N-hydroxyethylimidazole precursors via a ring-opening reaction from substituted imidazoles with ethylene carbonate, a 'green' substance formed from CO 2 and ethylene oxide. For the synthesis of 1-methyl-2-vinylimidazole, the hydroxyethylimidazole intermediate is conveniently formed from 1,2-dimethylimidazole and paraformaldehyde. These hydroxyethylimidazoles are subsequently dehydrated to the corresponding 1-or 2-vinylimidazole forms using a base-catalyzed reactive distillation. The optimization of process conditions is discussed, and properties of the vinylimidazole derivatives were computationally studied using density functional theory calculations. This work reveals scalable synthetic methods for previously inaccessible vinylimidazole compounds which can enable the design of new polymers.

Drinking water—a vital part of our ecosystem—is often exposed to contamination through industrialization. Halogenated compounds, for example, trihalomethanes (THMs), are among the most common contaminants, being by‐products of water chlorination/treatment. The carcinogenic and health effects of these compounds have motivated scientists to work on the accurate detection of THMs down to 80 ppb in treated water. Here, a superhydrophobic syndiotactic polypropylene (sPP) nanofiber mat is used to preconcentrate THMs in environmental water samples, and subsequently, detect them using a well‐known colorimetric reaction chemistry. The reaction chemistry yields a visible red/pink chromophore under visible light absorption. This reaction occurs when the preconcentrated THM becomes trapped in the liquid phase of the reaction chemistry, on the surface of the sPP fibers. This fiber mat is electrospun in a way which results in a large water contact angle >150°—allowing the working sensitivity of the reaction chemistry to be heightened and lowering the detection limit. The resulting color change can be analyzed via a simple quantitative color intensity analysis utilizing widely‐available software, measuring the THM content in water as low as 0.8 ppb. This cost‐effective and selective method was incorporated into a portable device, enabling on‐site users to evaluate the quality of drinking water.