28126-40-1Relevant academic research and scientific papers
Thiocarbamate-based synthesis of 2,4,5,6-tetrahydro-3H-1,2,4-triazepine-3-thiones
Trafimova, Ludmila A.,Zimin, Maxim O.,Shutalev, Anatoly D.
, p. 149 - 156 (2017)
A five-step synthesis of 5,7-diaryl-substituted 2,4,5,6-tetrahydro-3H-1,2,4-triazepine-3-thiones starting from ethyl thiocarbamate was developed. The synthesis included a three-component condensation of ethyl thiocarbamate with aromatic aldehydes and p-toluenesulfinic acid to give O-ethyl[(aryl)(tosyl)methyl]thiocarbamates which were transformed into the corresponding O-ethyl (3-phenyl-3-oxopropyl) thiocarbamates by treatment with the sodium enolate of dibenzoylmethane followed by base-promoted retro-Claisen condensation. Reaction of the prepared thiocarbamates with hydrazine and subsequent acid-catalysed cyclisation of the derived 4-[(3-hydrazono-3-phenyl)prop-1-yl]semicarbazides gave the target triazepines.
