The chemistry of Te, N-containing heterocycles has found considerable interest in the recent past, notably after 1,3-benzotellurazoles, 2,5-telluradiazoles and 1,2-tellurazole-N-oxide were found to self-assemble to supramolecular aggregates such as chains and macrocycles. Our work focusses on gaining improved access to 1,3-benzotellurazoles, as well as extending the range of known Te, N-containing heterocycles to include derivatives of 1,4-tellurazines and tellurazepines. 1,3-Benzotellurazoles are characterized by a remarkable stability to air and light, making them attractive targets for the synthesis of supramolecular frameworks. The main challenge concerning the preparation of five- to seven-membered Te, N-containing heterocycles is the fact that the synthesis of their sulfur congeners cannot be adapted to tellurium without major modifications. Significant difficulties where encountered during cyclization steps, notably due to competitive C-Te bond fission and reductive dehalogenation, which required optimized conditions to minimize. Strategies will be presented for the preparation of the target compounds, starting with bis(2-aminophenyl) ditelluride and its derivatives. It was found that the nature of substituents in position 2 of 1,3-benzotallurazole derivatives significantly influences their tendency to self-aggregate. The formation of supramolecular frameworks via C-N interaction was found to be in competition with that of dimers.

Advances in the synthesis of Te, N-containing heterocycles: Potential building blocks for supramolecular frameworks

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.