2,4,6,8-тетраметил-2 ,4,6,8-tetravinylcyclotetrasiloxane

Химические свойства

Colorless transparent liquid

Физические свойства

bp 224–224.5 °C.

Использование

2,4,6,8-Tetraethenyl-2,4,6,8-tetramethylcyclotetrasiloxane (1) (D4V) and the trimer, 2,4,6-triethenyl-2,4,6- trimethylcyclotrisiloxane (2) (D3V) are the two commercially available cyclic polyvinylmethylsiloxanes. D4 V is used as a vinyl donor in the palladium-catalyzed vinylation of aryl halides and as a building block in polymer chemistry and dendrimer synthesis. The palladium-catalyzed vinylation of substituted aryl halides using D4 V is a general and mild method for the preparation of a variety of substituted styrenes or dienes.It is widely used as reagent for the vinylation of aryl halides and building block for carbosilane dendrimers.

Общее описание

In the presence of a Pd catalyst, this reagent cross-couples with aryl bromides to give styrene derivatives.

Опасность

Low toxicity by ingestion and inhalation.

Методы очистки

A 7mL sample can be distilled in a small Vigreux column (p 11) at atmospheric pressure without polymerisation or decomposition. It is soluble in cyclohexane. [Kantor et al. J Am Chem Soc 77 1685 1955, Beilstein 4 IV 4184.]