3449-24-9Relevant articles and documents
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.
