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Updated: Nov 30, 2025

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Interconversion between a planar 1,3-dichlorobicyclo[1.1.0]tetrasilane and a (chloro)(chlorosilyl)cyclotrisilene
Takumi Nukazawa1, Takeaki Iwamoto
1Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku, Sendai 980-8578, Japan. takeaki.iwamoto@tohoku.ac.jp.
Abstract:
Heavy element analogues of bicyclo[1.1.0]butane have attracted much attention as they often exhibit skeletal isomerisations that are not observed for all-carbon bicyclo[1.1.0]butanes. The reaction of a bicyclo[1.1.0]tetrasil-1(3)-ene with CCl4 at low temperature provided orange crystals of a 1,3-dichlorobicyclo[1.1.0]tetrasilane containing a planar Si4 ring with a π-type bridgehead Si-Si bond. The equilibrium between the bicyclotetrasilane and an isomer, 1-chloro-2-(chlorosilyl)cyclotrisilene in solution, which is an unprecedented interconversion mode of Si4R6 isomers, was identified by NMR spectroscopy and also the formation of its 4-(dimethylamino)pyridine (DMAP) complex.
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