Quantitative 13C NMR provides a straightforward method of analyzing edible oils in undergraduate chemistry laboratories. 13C spectra are relatively easy to understand, and are much simpler to analyze and workup than corresponding 1H spectra. Average chain length, degree of saturation, and average polyunsaturated fatty acid content of common edible oils are obtained directly using integrals of the proper regions in the 13C 1D spectra. These spectra segue to 2D 1H–13C HSQC experiments that provide an excellent path for students to verify assignments, in particular those associated with polyunsaturated fatty acids. Data acquisition and analysis can be completed in one to two lab sections, although spectrometer scheduling may be necessary for groups of students greater than six. 13C relaxation measurements of common oils are presented that enable accurate quantitative 13C data to be obtained in reasonable amounts of time (30–40 min per sample) on modern 400 MHz NMR spectrometers.

An inexpensive procedure for introducing the Suzuki–Miyaura coupling reaction into a high-enrollment undergraduate organic chemistry laboratory course is described. The procedure employs an aqueous palladium solution as the catalyst and a range of para-substituted aryl bromides and arylboronic acids as substrates. The coupling reactions proceed rapidly at room temperature using standard glassware and do not require ligands, an inert atmosphere, or specialized equipment. Computational chemistry is used to explore the molecular and electronic structures of typical starting materials and products of the Suzuki–Miyaura coupling.

Bacterial resistance to current antibiotics is a major global health threat. Consequently, there is an urgent need for the identification of new antibacterial agents. We are applying the small-molecule macroarray platform to rapidly synthesize and screen compounds for activity against methicillin-resistant Staphylococcus aureus (MRSA). Herein, we report the synthesis of a 1,3-diphenyl-2-propen-1-one (chalcone) macroarray using a Rink-amide linker-derivatized cellulose support. The Rink linker allowed for the incorporation of a broader array of library building blocks relative to our previous syntheses because milder reaction conditions could be utilized; significantly higher compound loadings were also achieved (~80% vs ~15%). Analysis of the 174-member chalcone macroarray in off-support antibacterial screening assays revealed three chalcones with minimum inhibitory concentration (MIC) values against MRSA comparable to currently used antibacterial drugs and low hemolytic activities. These results serve to further showcase and extend the utility of the small molecule macroarray for antibacterial discovery.

By interfacing a digital camera with a scientific microwave unit it is possible to monitor macroscopic effects as reactions proceed, including color and viscosity changes, evolution of gases, metal-mediated couplings, and arcing.

In this report, we look at a range of classes of reaction involving microwave heating and show how different processing techniques can be used to address scale-up needs. We look at both batch and continuous-flow processing. We have shown that when using batch methodologies working using an open reaction vessel offers operational advantages while still giving good yields of desired products. In cases where open-vessel conditions are not amenable or where particularly volatile or toxic reagents are used, parallel sealed vessels can offer an alternative approach. For continuous-flow processing, homogeneity of the reaction mixture is key. When the mixture is homogeneous, it is possible to move from small-scale sealed-vessel conditions to the continuous-How apparatus without any modification of reaction conditions or loss in product yield. When either the starting materials or the product mixture contains particulate matter, continuous processing can prove a challenge, but reoptimization of reaction conditions as well as reduction of the concentration may allow these difficulties to be overcome.

A range of synthetic transformations have been scaled up successfully using a sealed-vessel multimode microwave unit. These include metal-catalyzed couplings, synthesis of heterocycles, reactions under an atmosphere of reactive gas and two-step one-pot procedures. Also, observations have been made along the way that are of use to chemists addressing scale-up of microwave-promoted reactions.

There is an urgent, global need for the development of new antibacterial agents. We have applied the small-molecule macroarray approach to the synthesis and screening of antibacterial compounds active against the Gram-positive pathogen Staphylococcus aureus. Several macroarrays of 1,3-diphenyl-2-propen-1-ones (chalcones), cyanopyridines, and pyrimidines were synthesized on a planar cellulose support system on the order of days. This support system was found to be highly compatible with antibacterial assay formats, including disk-diffusion and agar-overlay visualization methods. Further, sufficient compound was isolated from each spot of the macroarray for both compound characterization and minimum inhibitory concentration (MIC) estimation. Analysis of the small-molecule macroarrays in these assays uncovered a set of antibacterial agents with in vitro MIC values against methicillin-resistant S. aureus comparable to certain antibacterial drugs in use today.

We report a method for the efficient construction of small molecule macroarrays using microwave-assisted SPOT-synthesis. Macroarrays of 1,3-diphenylpropenones (chalcones) were synthesized rapidly and in high purity starting from robust, Wang-linker-derivatized planar supports. We have optimized the entire chalcone macroarray construction process and evaluated the efficiency and utility of microwave-assisted reactions in array synthesis. Microwave heating was found to be most beneficial for reactions that require temperatures greater than the boiling points of the solvents. These microwave-assisted conditions permitted straightforward access to macroarrays of 2,4,6-triarylpyridines derived from the original chalcone scaffold.

[structure: see text] Small molecule macroarrays of cyanopyridines and deazalumazines were generated in high purities via spatially addressed synthesis on planar cellulose supports. Examination of the spectral properties of the heterocycles both on and off of the planar support revealed a set of promising new fluorescent dyes that exhibit high quantum yields, low pH dependence, and high sensitivity to solvent polarity.

We demonstrate that microwave irradiation can dramatically accelerate reaction rates for spatially addressable library synthesis on planar membrane supports. The development of a robust support/linker system, microwave-assisted synthesis of small molecule test libraries, and methods for solid-phase scale-up on cellulose are described.

At the National Meeting of the American Chemical Society in Philadelphia on August 23–24, 2004, a Presidential Symposium Event was held titled "Responses to Changing Needs in U.S. Doctoral Education". This article provides a report of this two-day symposium, which featured an overview of the history and development of doctoral education in chemistry in the U.S., a description of social and cultural contexts that are influencing the field, an introduction to the reform projects being undertaken by departments of chemistry that are participating in the Carnegie Initiative on the Doctorate, and some perceptions of doctoral education from current graduate students in chemistry.