Using trimethoxysilane (TMSH) and hexene as raw materials, n-hexyltrimethoxysilane was synthesized via hydrosilylation. Two co-catalysts (nitrogen and phosphorus compounds) were added to the chloroplatinic acid complex to adjust the selectivity and reaction rate of the addition reaction. The reaction formula for the preparation of n-hexyltrimethoxysilane is shown in the figure below:
Figure 1. Reaction formula for the preparation of n-hexyltrimethoxysilane
Method 1:
First, dehydrate and dry the raw materials using molecular sieves for 24 hours. Weigh 69.2 g (0.20 mol) hexene, 0.692 g catalyst (catalyst platinum content is 5000 ppm, Pt to olefin mass ratio is 1:20000), and 29.8 g (0.22 mol) trimethoxysilane. The catalyst and reactants must be completely mixed and kept dry, isolated from water. Drying is carried out in an autoclave under vacuum.
Using negative pressure, the reactants are drawn into the reaction vessel and sealed. The temperature is raised to 120℃ and maintained for 2 hours. The reaction is exothermic; the temperature difference is controlled to not exceed 20℃. After 2 hours, the temperature is increased to 140℃ and maintained for 2 hours. After the reaction is complete and cooled to room temperature, the product is discharged, purified by distillation, and subjected to gas chromatography analysis of the product, n-hexyltrimethoxysilane. Method Two, Main Reagents and Instruments: Trimethoxysilane; Hexene; Chloroplatinic acid; Heated magnetic stirrer: DF-101S; Gas chromatograph: GC-14D (Shanghai Precision Scientific Instruments Co., Ltd.); Gas chromatography-mass spectrometry (GC-MS): HP-6890GC/5973MS (HP Corporation).
