Electrophilic aromatic substitution of 4-methoxyarylamines 2by the tricarbonyliron-complexed cyclohexadienylium cations 1leading to the iron complexes 3 is described. Chemoselectiveoxidation of the arylamine moiety of the complexes 3 to the quinoneimine and iron-mediated quinone imine cyclization using appropriate oxidizingreagents (activated manganese dioxide or thallium(III) trifluoroacetate) ledto the tricarbonyliron-complexed 4b,8a-dihydrocarbazol-3-ones 5.Demetalation of 5 with trimethylamine N-oxideat room temperature occurred with concomitant aromatization of the organicligand and provided a broad access to the 3-hydroxy-9H-carbazoles 7.
TEMPO-mediated late stage photochemical hydroxylation of biaryl sulfonium salts
作者:Yue Zhao、Congjun Yu、Wenjing Liang、Iuliana L. Atodiresei、Frederic W. Patureau
DOI:10.1039/d1cc07057f
日期:——
The late stage photochemical hydroxylation of biaryl sulfonium salts was enabled with a TEMPO derivative as a simple oxygen source, in metal free conditions.