Isopropanol → 2-Methylphenethylpentamethyldisiloxane

Participants

Reaction Conditions

Reaction Steps

The following were charged to a 1 L roundbottom flask equipped with stirrer, thermometer, and addition funnel and heated to 70° C: 375 g (3.15 mol) alpha-methylstyrene and 0.6 mL 1% isopropanolic chloroplatinic acid solution. 285 g (3.0 mol) dimethylchlorosilane was then dripped in from the addition funnel over 1 hour. The reaction was subsequently maintained at 80° C. for 1 hour and cooled. 212 g (1.0 mol) of the 2-methylphenethyldimethylchlorosilane product and 196 g (1.8 mol) trimethylchlorosilane were dripped into a mixture of 300 g water and 100 g isopropyl alcohol. The resulting reaction mixture was washed with water 3 times, the water (lower) layer was removed, and the reaction mixture (upper layer) was heated in vacuo to give 190 g (71% of the theoretical yield) 2-methylphenethylpentamethyldisiloxane. This 2-methylphenethylpentamethyldisiloxane had a refractive index of 1.463. a viscosity of 2.1 centistokes, and a boiling point of 120° C./10 mmHg.

Provenance & Evidence