Over the past several decades, research has become a key component of the undergraduate curriculum. Indeed, there have been considerable efforts to prepare undergraduates to engage in authentic research experiences with educators developing various curricular and pedagogical changes as the catalysts for effective preparation. However, most institutions elect to innovate in the major-level courses, while remaining committed to the traditional approach in general chemistry that was designed decades ago and took hold in the 1950s. It is our assertion that this outdated approach limits the ability of undergraduates to gain early access to research while also diminishing the learning gains experienced by students once they begin in their research endeavor. Therefore, in order to provide an alternative and potentially innovative approach to General Chemistry undergraduate education, we have explored the development of a combined lecture-laboratory course at the US Air Force Academy that emphasizes a research-forward, primary literature-based design to in lieu of the traditional textbook approach. This course emphasizes the extensive use of primary literature that is overtly connected to a series of experiments as the major emphasis in the course. As such, this course leans predominantly toward a laboratory-based method of instruction (∼70%). What follows is a description of a course, including methodology for changing the general chemistry curriculum from a course focused on distributing knowledge to one designed around introducing students to the academic chemical research process. This approach facilitates student learning relative to research, inquiry, and scientific reasoning, allowing such a curriculum format to be used for the achievement of relevant, in situ learning of chemistry.

Student engaged learning has been at the forefront of chemical education for the past several decades. Improving student engagement leads to increased retention of information being presented in lecture and laboratory-based settings. With this goal in mind, three laboratory-based learning modules were developed to address difficult learning areas in organic chemistry (acid/base/extractions, substitution reactions, and aromaticity). These data-driven modules focus on students using critical thinking skills to analyze data and answer guided questions in these trouble areas. The implementation of modules and an evaluation of effectiveness are presented.

Abstract Vermiculite clays are adsorbent materials that have good chemical adsorption capacity, which makes them applicable in the removal of drugs from aqueous solutions. Their lamellar structure can be easily expanded and organophilized. To assess the efficacy and environmentally-tolerant capacity of the adsorption method, the organophilized vermiculite clay was compared to both natural and expanded vermiculite clays. To prepare the organophilized clays, a natural clay sample was expanded at 900 °C. The expanded clay was thus treated by immersion in a 1.0 M NaCl solution and organophilized using a cetyltrimethylammonium bromide (CTMA-Br) surfactant, for 24 h at 50 °C. Natural, expanded, and organophilized samples were characterized using the techniques of XRD, FTIR, TG/DSC, and SEM to observe structural changes after expansion and organophilization. These characterizations indicated that there was an increase in the interlamellar space of the expanded and organophilized sample. In addition, a study of the point of zero charge was performed to determine the surface changes of the samples and the amount of doxazosin adsorption in the samples was determined by the time adsorption test. Further, the organophilized sample showed potential adsorption of the drug doxazosin and high performance in relation to the expanded and natural samples.

Abstract Clay is a material that exhibits excellent adsorbent properties which can be applied for the clarification of used motor oils. We describe a comparative analysis between natural and chemically-modified clays as an environmentally sound method of clarification. Previously, a sample of clay was chemically treated with KOH and H2SO4 with a concentration of 2.0 M at 150 °C. Both the natural and chemically-treated samples were characterized using the techniques of XRD, FTIR, SSA, and thermal analysis to observe the structural change after the chemical treatment. These characterizations indicated that there was an increase in surface area and microporous space creation in the acid-treated sample as a result of the clay exfoliation. The acid-treated sample exhibited the potential of clarification of waste oil and high performance relative to the natural sample and the base-treated sample.

Melamine is a key compound used as a clarifying agent for waste lubricating oil primarily due to its excellent adsorbent properties. Moreover, considerable interest exists for the further modification of melamine in order to provide a remediation agent with improved clarification capacity. In this study, hexamethylolmelamine was prepared using a solution of formaldehyde, which provided an agent capable of incorporation into a silicate polymer framework. Subsequently, the resultant monomer was added to a solution of silicate to produce the melamine-silica polymer. The melamine and melamine-silica polymer were characterized using the techniques of XRD, FTIR, SSA and thermal analysis to confirm structural and morphological characteristics. These characterizations indicated that the increase in the surface area of the 0.315 m2/g to melamine to 26.71 m2/g of melamine-silica suggests the effective introduction of silanols groups to hexamethylolmelamine and, therefore, corresponds to thehigh performance in relation to melamine as clarifying of waste lubricant oil.

The data in this article are related to the research article "Utilizing the Regioselectivity of Perfluoropyridine towards the Preparation of Phenyoxyacetylene Precursors for Partially Fluorinated Polymers of Diverse Architecture."(1) The X-ray structure analysis of 3,5-difluoro-2,6-bis(4-iodophenoxy)-4-phenoxypyridine has revealed an asymmetric unit containing two molecules, linked via both Type I and Type II C-I center dot center dot center dot I-C halogen bonding interactions. The packing is further consolidated via Ar-H center dot center dot center dot pi interactions. This compound has been utilized for the synthesis of monomers for linear and network polymers. Published by Elsevier Inc.

Regioselective nudeophilic substitution of perfluoropyridine with functionalized phenols provided a facile route toward the preparation of 2,6-bis(4-ethynylphenozy)-3,5-difluoro-4-phenoxypyridine, a monomer that can be polymerized neat via thermal [2 + 2 + 2] cyclopolymerizations affording intractable polyarylene networks or via copper-assisted step-growth 1,3-dipolar alkyne-azide "click" cycloaddition reactions with bis(azidomethyl) benzene. Both reactive pathways afforded polymers with high thermal stability and good char yields, which is comparable to acetylene-based resins. Notably, the opportunity for programmable thermal properties is realized through the operationally simple monomer synthesis was shown to be adaptive to various regioselective and nucleophile addition scenarios that can lead to the production of a library of perfluoropyridine monomers. Herein, we highlight the synthesis and characterization of these new perfluoropyridine-based polymer architectures for potentially tunable high performance applications.

Biodiesel is an important alternative fuel synthesized by the trans-esterification of vegetable oils, animal fats, and recycled greases. In this experiment, students prepared biodiesel through the base-catalyzed trans-esterification of several vegetable oils, which were subsequently analyzed in comparison with conventional petroleum-based fuels to assess their physical properties and to obtain a thermochemical profile. The experiment as described here could be employed by university faculty as a project in a major’s level laboratory course, but we envision the ideal fit to be a module within an advanced or integrated laboratory course. Students completing the project gain valuable experience in chemical synthesis and in extensive product characterization and analysis. This project reinforces critical skills in isolation of pure products from complex mixtures and in the careful preparation of samples for chemical analysis. Finally, students are afforded the opportunity to compare theoretical predictions fr...

Poly(phenylene vinylene) (PPV) represents an important class of conjugated, conducting polymers that have been readily exploited in the preparation of organic electronic materials. In this experiment, students prepare a PPV polymer via a facile multistep synthetic sequence with robust spectroscopic evaluation of synthetic intermediates and the final product. The synthetic sequence could be applied by university instructors as a capstone project for an undergraduate organic chemistry laboratory or as a centerpiece project for either a polymer or integrated laboratory course. The initial synthetic step could be segmented and used as a modular piece in the traditional introductory organic chemistry laboratory. In either case, the resultant PPV polymer is analyzed by UV-vis and fluorescence spectroscopy to determine the quantum yield which promotes enhanced student understanding of the photophysical properties of the material. In addition, GPC analysis is completed to reveal the molecular weight and polydispersity of the polymer. Students completing this experiment gain valuable experience in organic/polymer synthesis and structural characterization utilizing GC/MS, GPC, NMR, UV-vis, and fluorescence spectroscopy, as well as in the mechanistic aspects and practical application of some of the classic transformations in organic chemistry including the S(N)2 reaction, nucleophilic acyl substitution, organometallic chemistry, and Wittig reaction.

The identification of a predominate metabolite found in urine specimens which test positive for naphthoylindole-based synthetic cannabinoids is reported. The presence of this new metabolite was detected at the Air Force Drug Testing Lab Investigations Division during screening analysis for metabolites of JWH-018 and JWH-073, because it shares the same MRM transitions as the JWH-073 N-(3-hydroxybutyl) metabolite. However, the detected peak is chromatographically distinguished from other metabolites due to differences in retention time. This metabolite appears to be a common metabolite for select naphthoylindole-based synthetic cannabinoids that could potentially be used as a common biomarker for their qualitative and quantitative analyses. The new metabolite has been successfully identified as 3-(3-(1-naphthoyl)-1H-indol-1-yl) propanoic acid (1, JWH 072 N-propanoic acid metabolite, Fig. 1) by using various mass spectrometric and liquid chromatographic techniques as well as chemical derivatization. The metabolite identity was confirmed through the comparison of authentic positive urine and a chemically synthesized metabolite standard. Both materials shared the same chromatographic retention time on two separate chromatographic systems, mass fragmentation pattern and exact mass. Full characterization of the synthetic reference material and intermediates by (1)H NMR, (13)C NMR, IR and HRMS was also conducted.

A new class of partially fluorinated alternating aryl/alkyl vinylene ether (FAVE) polymers were prepared from addition polymerization of aryl trifluorovinyl ethers (TFVEs) with 1,4-butanediol or 4-hydroxybenzyl alcohol. Monodisperse FAVE telechelic polymerswere alsopreparedpossessing latent thermal reactivitywhich afforded chain-extendedperfluorocyclobutyl (PFCB) aryl ethers via step-growth [2+ 2] cyclodimerization of the aryl TFVEs. Both linear and PFCB chain-extended FAVE polymers produced thermally robust, optically transparent, flexible spin-cast films. The FAVE polymers and their telechelic polymers were characterized using 19F NMR and 1H NMR complemented with molecular weight analysis using gel permeation chromatography and thermal analysis employing differential scanning calorimetry and thermogravimetry. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.