1,1,3,3-Tetramethyl-disiloxane → 1-(Trimethoxysilyl)ethyl-1,1,3,3-tetramethyldisiloxane

Participants

Reaction Conditions

Reaction Steps

A four-necked flask equipped with a reflux condenser, stirrer, addition funnel and thermometer was thoroughly purged with nitrogen. In the nitrogen blanket, the flask was charged with 134.3 g (1 mol) of 1,1,3,3-tetramethyldisiloxane and 0.026 g (0.1 mmol) of RhCl3.3H2O to form a mixture. The mixture was heated to 60-70° C. and maintained at the temperature. With stirring, 148.2 g (1 mol, equimolar to 1,1,3,3-tetramethyldisiloxane) of vinyltrimethoxysilane was added dropwise to the mixture from the addition funnel over 6 to 7 hours. After the completion of dropwise addition, the reaction mixture was maintained at 60-70° C. and aged for 1 to 2 hours, driving the reaction to completion. On vacuum distillation, a product having a boiling point of 92-95° C. at 1.3 kPa was collected. The 1-(trimethoxysilyl)ethyl-1,1,3,3-tetramethyldisiloxane product was obtained in a yield of 93%. On gas chromatography analysis, the product was identified to be a mixture of two isomers, alpha-adduct:

Provenance & Evidence