146554-36-1Relevant academic research and scientific papers
A Comparsion between Zeolite-Solvent Slurry and Dry Solid Photolyses
Ramamurthy, V.,Corbin, D. R.,Turro, N. J.,Zhang, Z.,Garcia-Garibay, M. A.
, p. 255 - 261 (2007/10/02)
The use of zeolite-solvent slurry as a convenient medium to carry out photoreactions is illustrated with four examples, namely Norrish type I reaction of dibenzyl ketones, Norrish type I and type II reactions of α-alkylbenzyl benzyl ketones, Norrish type II reaction of aryl alkyl ketones, and photodimerization of acenaphthylene.Solvent present within the supercages of zeolites X and Y provides constraint on the mobility of the included guest molecules.Such restrictions are reflected in the product distributions.The difference in the product distribution obtained between the zeolite-solvent slurry and a homogeneous solution is often higher than that between the dry powder zeolites and a homogeneous solution.
Diffusion and percolation of radical pairs in zeolite media. A product analysis study
Garcia-Garibay, Miguel A.,Zhang, Zhenyu,Turro, Nicholas J.
, p. 6212 - 6218 (2007/10/02)
The photochemistry of dibenzyl-d5 ketone (DBK-d5) adsorbed in the zeolite NaX was investigated as a function of substrate loading. The cage effect and the relative yields of 1,2-diphenylethane (DPE), o-methyl-β-phenylacetophenone (o-MAP), and p-methyl-β-phenylacetophenone (p-MAP) were found to depend dramatically on the loading of the starting material present. These results and the variations observed in the percent cage effect are described in terms of local and global effects that determine the influence of the zeolite media. Changes in reactivity as a function of reactant loading are explained in terms of percolation theory by using the model "ants in a labyrinth" proposed by de Gennes. The diffusing radicals play the role of the ants and the disposition of the reactant in the regular zeolite topology determines the nature of the labyrinth. This model implies that the diffusion coefficient of the radicals is larger than the diffusion coefficient of the starting ketone. The model is supported by trapping experiments with an oxygen scavenger and by experiments carried out at -20 °C where the diffusion of the radicals is largely diminished.
