3424-57-5Relevant academic research and scientific papers
Alkyl and dialkylammonium tetrafluoroborate catalyzed cis-trans isomerization of 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane
Chang, Chiou-Ling,Leung, Man-Kit,Yang, Mei-Hui
, p. 9205 - 9212 (2004)
Alkyl and dialkylammonium tetrafluoroborate promoted cis-trans isomerization of 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane (1) in DMSO-d6 were studied. The isomerization equilibrium constant K are within the range of 3.74-3.30 from 22 to 4
A functionality do not contain impurity methyl phenyl cyclosiloxane method for the preparation of
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Paragraph 0048; 0049; 0054, (2017/04/29)
The invention relates to a preparation method of methylphenyl cyclosiloxane without containing polyfunctional impurities. The preparation method comprises the following steps: (A) sequentially adding a polar aprotic solvent, methylphenyl dialkoxysilane, water and a catalyst into a reactor for hydrolysis and condensation reaction, distilling out alcohol and water, and when the refractive index nD25 of distillate is nearly 1.3325, stopping the reaction; (2) gradually heating to 110-160 DEG C, and cracking the catalyst in a refluxing state; (3) after cracking the catalyst, distilling out and recycling the solvent, wherein an undistilled part in the reactor is a crude product; (4) distilling and purifying the crude product, and collecting methylphenyl cyclosiloxane distillate, namely obtaining a finished product. In the whole process, organic acid, inorganic acid or an alkali metal hydroxide is not used as a catalyst, and complex operations, such as neutralizing, water washing, filtering and the like rare not required; the reaction is easy to control; the yield of the finished product is as high as 90.0-97.1%; the purity of the finished product is 98.1-99.99%.
