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The thermal decomposition of dialkyl £er£-butylperoxy phosphates, in the presence and absence of solvents, yields the corresponding dialkyl phosphate, acetone, methanol, 2,2-dimethoxypropane, and methyl isopropenyl ether as the primary products. Prolonged heating of the product mixture produces trialkyl phosphates, (R0)3P(0), which arise from the thermal decomposition of dialkyl phosphates. Data are presented to support a mechanism involving the heterolytic cleavage of the peroxide linkage.

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The preparation of dialkyl tert-butylperoxy phosphates (2, R = alkyl) has been achieved by the reaction of the corresponding dialkyl phosphorochloridates (1, R = alkyl) with tert-butyl hydroperoxide either in the presence of pyridine or in the presence of aqueous potassium hydroxide solution. Neither of these routes is suitable for the preparation of dialkyl tert-butylperoxy phosphates in quantity since they yield peroxyphosphates which are contaminated either with the corresponding tetraalkyl pyrophosphates or dialkyl phosphates; the contaminants cannot easily be removed by conventional means from the peroxyphosphates. The method of choice for the preparation in high yield of large quantities of pure dialkyl tert-butylperoxy phosphates involves the interaction of the corresponding dialkyl phosphorochloridate with sodium tert-butyl peroxide which has been prepared in situ from the reaction of tert-butyl hydroperoxide with sodium hydride.

Reactions of alkyl ZerZ-butylperoxy alkylphosphonates (1), dialkyl ZerZ-butylperoxy phosphates (2), and other phosphorus compounds of general structure 3 [R = alkyl; R' = alkyl, alkoxy; X = OR, OH, H, Cl, 0P(0)R'(0R), OCMes] with benzene in the presence of aluminum chloride proceed rapidly at 5°to produce primarily the corresponding monoalkyl benzene derived from cleavage of the P • • • O • • R linkage of the phosphorus compound. In the cases of 1 and 2, ZerZ-butylbenzene and phenol are also found, derived from cleavage of the peroxide linkage. Reactions of dialkyl ZerZ-butylperoxy phosphates (2) with phenylmagnesium bromide produce high yields of ZerZ-butyl phenyl ether and moderate to high yields of the corresponding dialkylphosphoric acid 8.