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Updated: May 18, 2026

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Catalytic trimerization of bis-silylated diazomethane
Muhammad Farooq Ibad1, Peter Langer, Fabian Reiß
1Abteilung Anorganische Chemie, Institut für Chemie, Universität Rostock, Albert-Einstein-Straße 3a, D-18059 Rostock, Germany.
Abstract:
(Me(3)Si)(2)CNN isomerizes upon addition of traces of [Me(3)Si](+) ions to give (Me(3)Si)(2)NNC, which then undergoes an unusual trimerization reaction to give exclusively 4-diazenyl-3-hydrazinylpyrazole. As catalyst the isonitrilium ion, [(Me(3)Si)(2)NNC(SiMe(3))](+), was identified and fully characterized. Experiments and computations indicate a three-step reaction including isomerization of diazomethane, a C-C or N-C coupling, and a formal cycloaddition reaction. The kinetics and thermodynamics are discussed on the basis of DFT calculations.
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