Competitive cyclisations of singlet and triplet nitrenes. Part 5. Mechanism of cyclisation of 2-nitrenobiphenyls and related systems

Thermal decomposition of o-azidobithienyls

“…Finally, although satisfactory elemental analyses could not be obtained for compounds (11) and (111) because of their instability, the values obtained were close to those expected for rn-dithiin structures (10). Since these data appear to be consistent with both tautomeric structures (10A) and (10B) (including their geometrical isomers) a definite structure is not assigned to the isomers (11) and (111).…”

“…The main products isolated from decomposition of the azide (3, after chromatographic separation, were two rather unstable oily compounds (11) and (111) which probably were two rn-dithiin isomers (lo), arising through a remarkable ring-opening of the azide ( 5 ) and subsequent cyclodimerization of the resulting ene-thione (9), according to the outlined sequence :…”

Intramolecular Aromatic Amination through Iron‐Mediated Nitrene Transfer

“…Nitrene insertions to give aliphatic CH bond aminations have also been effected by metalloporphyrins or cytochrome P450 5. 6 In contrast, metal‐catalyzed arene amination is practically unknown,6 even though free organonitrenes will readily add to aromatics 7. Substoichiometric and unselective naphthalene amination by an uncharacterized adduct of iron( II ) chloride and chloramine‐T has been reported,8 along with a handful of possibly analogous organometallic ligand transformations 9.…”

Intramolecular Aromatic Amination through Iron‐Mediated Nitrene Transfer

“…[5,6] In contrast, metal-catalyzed arene amination is practically unknown, [6] even though free organonitrenes will readily add to aromatics. [7] Substoichiometric and unselective naphthalene amination by an uncharacterized adduct of iron(ii) chloride and chloramine-T has been reported, [8] along with a handful of possibly analogous organometallic ligand transformations.…”