regions were integrated and simple relationships were used to extract the da/di ratios. For example, with mixtures of propene-¿0 and -2-d¡, the resonances at 5.82 arise from the d0 species while the multiplets at either 4.93 or 5.02 can be used to determine the 0 and 2-d¡ sum. For mixtures of propene-íf0 and (£)-propene•./-^, the resonances at 4.93 arise from the ¿1 species while either of the other two multiplets downfield determine the d0 and if, sum. The relative intensities of the l0i -*• 202 and 110 -* 2n microwave transitions of the normal and both deuterated species of propylene were also used to determine the da/dx ratios.36•37 These transitions are split into partially resolved doublets due to methyl tunneling effects so the intensity ratios were evaluated by cutting and weighing. Base-line problems are accentuated by this procedure and contribute to some of the data scatter. The NMR analysis of the propylene ozonide was carried out in a manner similar to that of propylene. These data were used in relationships previously discussed to determine kH/kD.ls Acknowledgment. We are grateful to Frank Parker who was invaluable in obtaining NMR spectra, Dr. Misako Imachi who provided the (£)-propene-7-,, and Dr. Kurt Hillig who advised on ozonolysis techniques. This work was supported by Grant CHE-8005471 from the National Science Foundation.
The photooxidation of the antipsoriatic drug anthralin (1,8-dihydroxy-9-anthrone) has been studied by several kinetic techniques, including direct observation of 1O2 (1 delta g) luminescence at 1.27 microns. The rate of deactivation of 1O2 increases at higher pH, demonstrating that the trihydroxyanthracene anion is the reactive species. Direct determination of the rate constant of 1O2 deactivation (kR + kQ) in deuterated buffer systems by luminescence quenching gave a value of 3.0 x 10(8) M-1 s-1 for the anion; the neutral anthrone is unreactive. The rate constant for the neutral anthrone in benzene-d6 is 2.8 x 10(4) M-1 s-1. Competition experiments with tetramethylethylene in acetonitrile gave a rate constant for reaction alone (kR) of 2.1 x 10(8) M-1 s-1 for the anion.
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