双三苯基硅烷铬酸酯合成工艺研究

以三苯基氯硅烷和重铬酸钾为原料合成双三苯基硅烷铬酸酯，研究溶剂对反应的影响，发现冰醋酸对该SN1-Si取代反应具有促进作用，采用混合溶剂体系，减少了溶剂对环境的污染，改进了后处理过程，提高了产品纯度。通过正交试验确定了最适宜合成工艺条件：反应温度30屯，反应时间2h，n（三苯基氯硅烷）：n（重铬酸钾）为2．O：1．2，V（冰醋酸）：V（环己烷）为2：1。该条件下合成产品收率在79％以上，熔点155～156℃，元素、DSC、红外分析结果证明产品结构与目标产物基本相符。

Synthesis Technology for Bistriphenylsilyl Chromate

Bistriphenylsilyl chromate was prepared from triphenyl chlorosilane and potassium dichromate. The effect of solvent on the reaction was studied and found glacial acetic acid as solvent could promote substitution reaction of SN1-si. Binary solvent was chosen to improve the post-processing method and the product purity, and to reduce pollution to environment. The optimized conditions for synthesizing were as follows：the reaction temperature was 30 ℃, the reaction time was 2 h,the molar ratio of triphenyl chlo- rosilane to potassium dichromate was 2.0; 1.2,the volume ratio of glacial acetic acid to cyclohexane was 2： 1. Under the optimal condition,the yield of star antioxidant was above 79% and the melting point was 155--156 ℃. The structure was characterized by elemental analysis,DSC and IR.