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The proton NMR spectra of aryl n-propyl sulfides gave rise to what may appear to be first-order proton NMR spectra. Upon oxidation to the corresponding sulfone, the spectra changed appearance dramatically and were clearly second-order. A detailed analysis of these second-order spectra, in the sulfone series, provided vicinal coupling constants which indicated that these compounds had a moderate preference for the anti-conformer, reflecting the much greater size of the sulfone over the sulfide. It also emerged, from this study, that the criterion for observing large second-order effects in the proton NMR spectra of 1,2-disubstituted ethanes was that the difference in vicinal coupling constants must be large and the difference in geminal coupling constants must be small. n-Propyl triphenylphosphonium bromide and 2-trimethylsilylethanesulfonyl chloride, and derivatives thereof, also exhibited second-order spectra, again due to the bulky substituents. Since these spectra are second-order due to magnetic nonequivalence of the nuclei in question, not chemical shifts, the proton spectra are perpetually second-order and can never be rendered first-order by using higher field NMR spectrometers.

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The anisotropy of nonwoven fabrics of various types has been studied in terms of modulus, strength, breaking extension, and fiber orientation. Polar diagrams for these quantities are given. Another important factor is the degree of curl in the fibers, and results are compared from different types of fabric and different directions. The variations in mechanical properties with direction are explained in terms of the structural features.

cis-Dihydrocatechols, derived from biological cis-dihydroxylation of methyl benzoate, iodobenzene and benzonitrile, using the microorganism Pseudomonas putida UV4, were converted into pericosines A, C, and B, respectively. This approach constitutes the shortest syntheses, to date, of these important natural products with densely packed functionalities.

A theory of the resistance to extension of nonwoven fabries is calculated on the as sumption that they behave as boaded fiber networks. Early work by Petterson has been generahzed to indude the ettects of fiber curl. which is shown to have a great effect on the value of the initial modulus. There is a good measure of agreement with ex petimental results.