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The microwave spectrum of 4-fluoro-1-butene has been reinvestigated in the 10-26.5 GHz spectral range. The ground and several vibrationally excited states have been assigned for two «new» rotamers denoted Skew-Gauche I and Skew-Gauche II. The dipole moments of the «new» conformers have been determined

α-Values evaluated from solvent deuterium isotope effects and excess acidity correlations have been observed to be very similar in the acid-catalyzed hydrations of both norbornenes (0.77±0.11 and 0.77±0.05, respectively) and nortricyclanes (0.78±0.15 and 0.80±0.03, respectively). By using these, together with reaction constants, the α-values were also estimated for the solvolyses of 2-norbornyl tosylates. They are reasonable (0.88±0.10) if the first-formed carbocations are of similar character in the solvolyses and hydrations, but unreasonable if their characters are different

CASPER, a computer program by which structural analysis of polysaccharides can be performed, has been tested for accuracy. This was done by simulation of the 1 H and 13 C NMR spectra of the Shigella flexneri type Y O-polysaccharide using data from the constituent disaccharides and then comparing these with experimental data. A close fit between experimental and calculated 1 H and 13 C NMR spectra was observed. Conformational and NMR studies on the disaccharides, as methyl glycosides, were also performed. Furthermore, an extraction procedure, aimed at improving the database in CASPER is demonstrated

The mechanism of oxidative decarboxylation of 2-hydroxy-2-phenylethanoic acid (mandelic acid) by aqueous alkaline sodium hypochlorite (commercial bleach) has been studied. Kinetic studies for a series of 4-substituted mandelic acids (CH 3 O, CH 3 , H, F, Cl, CF 3 , NO 2 substituents) gave a Hammett o value of −0.23. When deuterium was substituted for hydrogen on the α-carbon atom of mandelic acid, a secondary kinetic isotope effect, (k H /k D ), of 1.07 was obtained. On the basis of these results a model for the transition state is proposed