Bhanuchandra, M. published the artcileTransition-Metal-Free Synthesis of Carbazoles and Indoles by an SNAr-Based “Aromatic Metamorphosis” of Thiaarenes, Synthetic Route of 57103-14-7, the publication is Angewandte Chemie, International Edition (2015), 54(35), 10234-10238, database is CAplus and MEDLINE.
Dibenzothiophene dioxides, e.g. I, which are readily prepared through oxidation of the parent dibenzothiophenes, undergo nucleophilic aromatic substitution with anilines RNH2 (R = Ph, 4-MeC6H4, 4-H2C:CHC6H4, 2,4,6-Me3C6H2, 1,3-benzodioxol-5-yl, etc.) intermolecularly and then intramolecularly to yield the corresponding carbazoles, e.g. II, in a single operation. The “aromatic metamorphosis” of dibenzothiophenes into carbazoles does not require any heavy metals. This strategy is also applicable to the synthesis of indoles. Since electron-deficient thiaarene dioxides exhibit interesting reactivity, which is not observed for that the corresponding electron-rich azaarenes, a combination of a thiaarene-dioxide-specific reaction with the SNAr-based aromatic metamorphosis allows transition-metal-free construction of difficult-to-prepare carbazoles.
Angewandte Chemie, International Edition published new progress about 57103-14-7. 57103-14-7 belongs to isoxazole, auxiliary class Fused Tricycles,Carbazoles, name is 9-(4-Fluorophenyl)-9H-carbazole, and the molecular formula is C18H12FN, Synthetic Route of 57103-14-7.
Referemce:
https://en.wikipedia.org/wiki/Isoxazole,
Isoxazole | C3H3NO – PubChem