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Updated: Jul 10, 2026

Characterization of Synthetic Polymers via Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) Mass Spectrometry
Published on: June 10, 2018
Dodecamethoxy- and hexaoxotricyclobutabenzene: synthesis and characterization
Toshiyuki Hamura1, Yousuke Ibusuki, Hidehiro Uekusa
1Interactive Research Center of Science, Department of Chemistry, Tokyo Institute of Technology, SORST, Japan Science and Technology Corporation (JST), O-okayama, Meguro-ku, Tokyo 152-8551, Japan.
Abstract:
We report herein the syntheses of dodecamethoxytricyclobutabenzene (TCBB) 1 and hexaoxo-TCBB 2, a class of molecules with structural and theoretical interest. The preparation is based on the 3-fold [2 + 2] cycloadditions of benzyne and ketene silyl acetals (KSAs), where the selectively protected 2-iodophloroglucinol derivative served as a synthetic equivalent of benztriyne I, allowing rapid and regioselective annulation of fully functionalized four-membered rings. Structural study on the former compound showed that the C-C bond lengths in the central benzene ring were essentially the same.
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