Comparative study on syntheses of 1,3,5-trimethoxy-1,3,5-triisopropylcyclotrisiloxane

Abstract

1,3,5-Trimethoxy-1,3,5-triisopropylcyclotrisiloxane (2) was prepared from 1,3,5-triisopropyl-1,3,5-tri-o-tolylcyclotrisiloxane—(1) according to three kinds of methods as follows: the dearylchlorination of 1 using HCl/AlCl3, which led to prepare 2 includes a very slight amount of aluminum species as impurities, the dearylbromination using Br2, which simultaneously brought unnecessary bromination without isolated 2, and the dearylation using TfOH, which efficiently gave 2 of a high purity without metals of contamination.