Synthesis of 1,2-Diazepines by the Bischler–Napieralski Reaction

NMR 1H Spectra of the [1,2]Diazepino[4,5-b]Indole Derivatives: Experimental versus GIAO calculated Data

“…With an increase in the temperature of the NMR experiment, one can expect higher conformation exchange rates, and, as a consequence, an even greater closing-in of these protons signals up to their coalescence. We observed such pattern for the 1,4-biaryl derivatives of benzofuro [2,3-d] [1,2]-diazepines experimental NMR 1 H spectra [17]. Thus, a comprehensive study of the 1,2-diazepine core dynamics of condensed diazepines by dynamic NMR spectroscopy as well as DFT method will be the next stage of our work.…”

Bischler‐Napieralski Cyclization: A Versatile Reaction towards Functional Aza‐PAHs and Their Conjugated Polymers†

“…Over the past century, Bischler‐ Napieralski cyclization has provided an efficient way to access libraries of structurally diversified nitrogen‐containing heterocyclic compounds with potential pharmaceutical or biological activities. [ 8‐9 ] For example, various benzodiazepines derivatives were obtained, such as pyrrolobenzo[ b ]thieno[1,4]diazepines, [ 10 ] tricyclic pyrimido[4,5‐ b ][1,4]benzothiazepines, [ 11 ] 5 H ‐[1]benzofuro[2,3‐ d ][1,2]diazepines, [ 12 ] 11 H ‐pyrimido[4,5‐ b ][1,4]benzodiazepines [ 13 ] and pyrrolo[1,2‐ a ][1,6]benzodiazonines. [ 14 ] Despite the high efficiency in C=N bond formation within aromatic rings via Bischler‐Napieralski cyclization, its utility in synthesizing aza‐PAHs was not recognized until 2010.…”