Ralph L. Dannley

Peroxides derived from dialkyltin derivatives

Abstract Dialkyltin dimethoxides yield insoluble (probably polymeric) peroxides in a high state of purity when treated with 98% hydrogen peroxide. If an aldehyde or ketone is present, a peroxide of the general formula (OCR′R″O 2 SnR 2 ) π is obtained. These peroxides associate in solution so that molecular weights are difficult to obtain, but the materials are predominantly simple heterocycles (n = 1) although appreciable quantities of macrocycles or linear polymers ( n > 1) may be present. The benzaldehyde dibutyltin peroxide (1.0 mole) decomposes thermally to (C 4 H 9 ) 2 SnO [0.84, isolated as (C 4 H 9 ) 2 SnCl 2 )], oxygen (0.31), benzaldehyde (0.29), and benzoic acid (0.35). These peroxides decompose thermally by first-order kinetics ( is 10 -2 to 10 -3 sec -1 ). E a is 23 kcal/mole for the dibutyltin benzaldehyde peroxide, E a is 18 kcal/mole for the valeraldehyde analogue. A good σ Hammett plot was obtained for the para -substituted benzaldehydes with a ρ of −0.43.