21116-72-3Relevant academic research and scientific papers
Preparation method of cyclodisilazane
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Paragraph 0087-0090, (2021/02/10)
The invention relates to a preparation method of a cyclodisilazane compound shown as a formula (I), which comprises the step of preparing cyclodisilazane shown as the formula (I) from a 1, 3-dihalodisilazane compound shown as a formula (II), wherein the formulas are described in the specification. Compared with a traditional high-temperature rearrangement method and a method for preparing 1, 3-bis(chlorodiorganosilyl) cyclodisilazane through high-temperature high-compression polymerization and exchange reaction, the preparation method of cyclodisilazane provided by the invention has the advantages of low reaction temperature, short reaction time, few byproducts, high yield and capability of efficiently preparing cyclodisilazane compounds with different structures; compared with a method of lithiating butyl lithium and then removing lithium chloride to form a reaction ring, the method has the advantages that the reaction can be completed in one step, the process is simple and easy to control, and the cost is low; and moreover, the preparation method is high in safety, easy to control, low in cost, environmentally friendly and beneficial to large-scale production.
Synthesis of 1,3-bis(chlorodiorganosilyl)-cyclodisilazane via dehydro-chlorination reaction of 1,3-dichloro-Tetraorgano-Disilazane in the presence of deacidification agent
Kong, Shuxuan,Li, Ning,Tan, Yongxia,Xie, Zemin,Zhang, Shuhao,Zhang, Xuezhong,Zhang, Zhijie
, (2020/07/30)
A novel convenient synthesis process for 1,3-bis(chlorodiorganosilyl)-cyclodisilazanes is developed via an intermolecular dehydrochlorination of 1,3-dichloro-tetraorgano-disilazane, in the presence of a strong organic alkaline deacidification agent 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). This procedure involves a one-step process under mild synthesis condition, with higher production efficiency and product purity as compared to those of the previously reported methods. The formation of 1,3-bis(chlorodiorganosilyl)-tetraorgano-cyclodisilazane occurs via the primary dehydrohalogenation of intermolecular 1,3-dichloro-tetraorgano-disilazanes to trisilylamine structure with a subsequent ring closure. The silicon atoms with different exocyclic or endocyclic substituents are closely related to the steric hindrance of the substituents. Dehydrochlorination reactions occur more readily on the chlorine atoms attached to the silicon atoms with substituents possessing relatively low steric hindrance. Four 1,3-dichloro-tetraorgano-disilazanes for the synthesis of 1,3-bis(chlorodiorganosilyl)-cyclodisilazanes are prepared. The investigation into the reaction mechanism shows that the equilibrium reaction of cyclosilazane with diorgano-dichlorosilane is a more straightforward and efficient method in the preparation of 1,3-dichloro-tetraorgano-disilazanes, as compared to the trans-silylation reaction of hexamethyl-disilazane with diorgano-dichlorosilane.
