The oxidation of a variety of triorganosilanes by dimethyldioxirane afforded the corresponding silanols in quantitative yield. The reactions are performed at room temperature using acetone or CCl4 as the solvent. Under similar conditions, (Me3Si)3SiH gave silanol in 80-90% yield together with other identified products. Rate constants for these reactions were measured by following the disappearance of the dimethyldioxirane absorption at 335nm. Depending on the substituents at the SiH moiety, the reactivities cover ca. 4 orders of magnitude (from 5.8 x 10(-3) M(-1) s(-1) for (Me3SiO)3SiH at 25 °C to 14.5 M(-1) s(-1) for (Me3-Si)3SiH at 15 °C). Arrhenius parameters were determined for a few representative substrates. The reaction mechanism in terms of a concerted oxygen insertion vs radical path is discussed in some detail.
Kinetic and Product Studies of the Reaction of Triorganosilanes with Dimethyldioxirane
Chatgilialoglu C
2002
Abstract
The oxidation of a variety of triorganosilanes by dimethyldioxirane afforded the corresponding silanols in quantitative yield. The reactions are performed at room temperature using acetone or CCl4 as the solvent. Under similar conditions, (Me3Si)3SiH gave silanol in 80-90% yield together with other identified products. Rate constants for these reactions were measured by following the disappearance of the dimethyldioxirane absorption at 335nm. Depending on the substituents at the SiH moiety, the reactivities cover ca. 4 orders of magnitude (from 5.8 x 10(-3) M(-1) s(-1) for (Me3SiO)3SiH at 25 °C to 14.5 M(-1) s(-1) for (Me3-Si)3SiH at 15 °C). Arrhenius parameters were determined for a few representative substrates. The reaction mechanism in terms of a concerted oxygen insertion vs radical path is discussed in some detail.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
