Tetraphenylethylene ozonization

Ozonolysis of Tetramethylethylene and Tetraphenylethylene. A solution of 0.259 gram (3.1 mmoles) of tetramethylethylene and 1.0 gram (3.1 mmoles) of tetraphenylethylene in 40 ml chloroform was ozonized to completion at room temperature. Chloroform was used as the solvent since tetraphenylethylene is fairly insoluble in pentane. Analysis of the reaction mixture by TLC and GPC showed only acetone diperoxide and benzophenone diperoxide to be present. 

One of our earlier attempts to form a cross diperoxide used a variation of olefin types 4 and 5. In this case equimolar amounts of tetra-phenylethylene, 6, and tetramethylethylene, 7, were ozonized together. While ultimately both acetone diperoxide and benzophenone diperoxide could be isolated from the reaction mixture, it became apparent that these olefins have such different reactivities toward ozone that the tetramethylethylene was selectively ozonized. Only after most of the tetramethylethylene had been ozonized was the tetraphenylethylene attacked. The opportunity for cross diperoxide formation in this case is thus minimal. 

Some trisubstituted ozonides could be obtained only by the method of Murray, Story, and Loan (1)—namely, the ozonization of disubstituted olefins in ketones as solvents. Ozonization of tetraphenylethylene in acetone, methyl ethyl ketone, or benzophenone gave the hitherto unknown trioxolanes with four hydrocarbon residues (2). Table I shows some examples. 

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