Tritium-Labeled Compounds IX. Determination of Isotope Effects in Reactions Yielding Water-f from Nonvolatile Reactants. Oxidation of Aldoses-1-t With Iodine
نویسندگان
چکیده
A convenient method is presented for est imating isotope effects in reactions which yield water-J. T h e water-2 is separated by freeze-drying, and k*/k is calculated from the extent of t he reaction and the rat io of the radioactivi ty of the water-Z to t h a t of the initial reac tant . Application of the method to the oxidation of aldoses-l-£ a t 25 °C with iodine in alkaline solution gives values for k*/k ranging from 0.12 to 0.17, with an average of 0.14. There are no significant differences in the values of k*/k obtained for aldoses differing in configuration, or for pentoses and hexoses. The isotope effect corresponds to a rat io of one t o seven for the respective rates of reaction of the labeled and unlabeled molecules.
منابع مشابه
Tritium-Labeled Compounds IX. Determination of Isotope Effects in Reactions Yielding Water-t from Nonvolatile Reactants. Oxidation of Aldoses-l-t With Iodine
A convenient m ethod is presented for estimating isotope effects in reactions which yield waterto The water-t is separated by freez e!=h~yjng, and k*/k is calculated froJ? .t!J.e extent of the reaction and the ratio of the radioactIvIty of t he water-t to that of the lnItlal reactant. Application of the method to the oxidation of aJdoses-1-t at 25°C with iodine in a lkaline solution gives value...
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