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The first asymmetric synthesis of the previously unknown (-)-methyl palustramate is reported. The stereoselective synthesis featured a conformationally restricted Claisen rearrangement methodology to produce 1-benzylpipecolic ester as well as a new approach for debenzylation of 1-benzylpiperidines to successfully remove the benzyl protecting group, which traditional methods failed to accomplish. Research is being conducted on the usse of the methodology to the synthesis of (+)-palustrine.

The naturally occurring indolizidine alkaloid (-)-indolizidine 167B was prepared in nine steps with a 5.8% overall yield from an amino ester. This synthesis illustrates the importance of the Claisen rearrangement technique for the preparation of enantiopure indolizidine alkaloids from readily available alpha-amino acids. Moreover, the preparation of (-)-indolizidine 167B demonstrates the short pathway to N-benzylpipecolic esters.

The Public Works Department of Newmarket, NH, collaborated with University of New Hampshire researchers to construct a salt storage facility that is resistant to chloride corrosion. The team used two-dimensional fiber-reinforced plastic to strengthen the six foot high concrete walls of the structure which also utilizes a hyperbolic shell. Fiber-reinforced plastic is usually more expensive than steel but it can be competitive when labor and design are included in the estimation. The project is in response to lower public maintenance budgets and stricter environmental regulations.

A magnetic microrheometer has been designed to characterize the local viscosity of liquid-applied coatings in situ during solidification. The apparatus includes NdFeB magnets mounted on computer-controlled micropositioners for the manipulation of ∼1 μm diameter superparamagnetic particles in the coating. Magnetic field gradients at 20-70 T/m are generated by changing magnet size and the gap distance between the magnets. A specimen stage located between two magnets is outfitted with a heater and channels to control process conditions (temperature and air flow), and a digital optical microscope lens above the stage is used to monitor the probe particle position. Validation studies with glycerol and polyimide precursor solution showed that microrheometry results match traditional bulk rheometry within an error of 5%. The viscosities of polyvinyl alcohol (PVA) solution and polyimide precursor solution coatings were measured at different shear rates (0.01-5 s-1) by adjusting the magnetic field gradient. The effect of proximity to the substrate on the particle motion was characterized and compared with theoretical predictions. The magnetic microrheometer was used to characterize the time-viscosity profile of PVA coatings during drying at several temperatures. The viscosity range measured by the apparatus was 0.1-20 Pa s during drying of coatings at temperatures between room temperature and 80 °C. [ABSTRACT FROM AUTHOR]