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Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
[1.1](3,3')-azobenzenophane: novel crystal structure and cis-trans isomerization of distorted azobenzene
Yasuo Norikane1, Kogorou Kitamoto, Nobuyuki Tamaoki
1Institute for Materials and Chemical Process, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1, Higashi, Tsukuba, Ibaraki, 305-8565, Japan.
Abstract:
[formula: see text] [1.1](3,3')-Azobenzenophane, in which two azobenzenes are cyclically connected by -CH2- chains at the meta positions, has been synthesized. The crystal structures of all isomers have been revealed. This is the first report on the crystal structure of the cis isomer of macrocyclic azobenzenes. The trans,trans isomer was slightly distorted, the trans,cis isomer highly deformed, and the cis,cis isomer unstrained. The thermal stability of cis isomers in solutions are deducible from the crystal structures.
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