Volatilization and Photodecomposition of Plictran Miticide

Abstract

Recently, a new organic tin product, Plictran miticide containing tricyclohexyltin hydroxide, has been developed for the control of mites in apples, pears, and citrus fruits. Photodecomposition and volatility studies were conducted with this miticide. The results indicate that tricyclohexyltin hydroxide rapidly undergoes photodecomposition, the main products being inorganic tin (80 %) with traces of dicyclohexyltin oxide, cyclohexylstannoic acid, and tricyclohexyltin hydroxide unchanged. The traces of tetracyclohexyltin which were present in the samples as an impurity were not affected by irradiation. The amount of tricyclohexyltin hydroxide depends on the length of exposure and the intensity of the sunlight. The longer the exposure and the more intense the light the more tricyclohexyltin hydroxide will be decomposed. Volatility studies indicate that tricyclohexyltin hydroxide is not volatile from the dry state, but that the compound can be lost from a moist surface by co-distillation. The rate at which the miticide will be lost depends on the temperature and quantity of water evaporated. The dicyclohexyltin oxide is volatile from the dry state and can co-distill with water.

Determination of triphenyltin hydroxide and its degradation products in water

“…From previous studies on other organotin compounds (10,11), it appeared that diphenyltin oxide (Ph2SnO, where Ph = phenyl), benzenestannoic acid (PhSn02H), and inorganic tin would be likely degradation products of triphenyltin hydroxide (Ph3SnOH). (Current Chemical Abstracts nomenclature as follows: PhSn02H, hydroxyoxophenyl stannane; Ph2SnO, oxodiphenyl stannane; PhgSnOH, hydroxytriphenyl stannane.)…”