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Updated: Jun 15, 2025
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
A Systematic Study of the Solid-State Pathway from Melamine via Melaminate to Carbodiimide under Evolution of
Markus Ströbele1, Elaheh Bayat1, Hans-Jürgen Meyer1
1Section for Solid State and Theoretical, Inorganic Chemistry, Institute of Inorganic Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
Abstract:
Thermal analysis techniques, such as differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), can provide valuable insights into thermal properties, intermediate phases, and phase transitions; sometimes even a whole series of compounds appears in a given system. The solid-state reaction pathway from melamine to carbodiimide, monitored by DSC, involves a sequence of chemical reactions and intermediate phases departing from the reaction of potassium hydride and melamine. The fully analyzed reaction cascade begins with the formation of potassium melaminate, K(C3N6H5), and progresses through several intermediate phases, each with distinct structures and properties, before ultimately yielding β-K2(CN2). All crystalline compounds appearing in this reaction sequence are identified using X-ray diffraction analyses. With a 6:1 ratio of potassium hydride and melamine, equal numbers of protic and hydridic hydrogen atoms in the starting materials favor the release of H2 until the formation of the final product K2(CN2), which appears with two modifications.
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