Categories: Synthesis of O-Heterocycles > benzo-fused O-Heterocycles >
Synthesis of Dibenzofurans
Name Reactions
Recent Literature
Palladium catalysis enables an intramolecular cyclisation of ortho-diazonium
salts of diaryl ethers to give dibenzofurans. The protocol uses 3 mol% palladium
acetate as the catalyst in refluxing ethanol in the absence of base.
Z. Du, J. Zhou, C. Si, W. Ma, Synlett, 2011,
3023-3025.
An intramolecular palladium(II)-catalyzed oxidative carbon-carbon bond formation
under air in the presence of pivalic acid as the reaction solvent, instead of
acetic acid, results in greater reproducibility, higher yields, and broader
substrate scope. The reaction allows the conversion of both electron-rich and
electron-deficient diarylamines.
B. Liégault, D. Lee, M. P. Huestis, D. R. Stuart, K. Fagnou, J. Org. Chem., 2008,
73, 5022-5028.
An efficient method for the synthesis of dibenzofurans from o-iododiaryl
ethers is catalyzed by reusable Pd/C under ligand-free conditions. Synthesis of
o-iododiaryl ether was achieved in one pot through sequential iodination
and O-arylation of phenol under mild reaction conditions.
N. Panda, I. Mattan, D. K. Nayak, J. Org. Chem.,
2015,
80, 6590-6597.
An efficient route to carbazoles and dibenzofurans has
been developed. The reaction of
o-iodoanilines or o-iodophenols with silylaryl triflates in the
presence of CsF to afford N- or O-arylated products is followed by
a cyclization using a Pd catalyst to carbazoles and dibenzofurans in good to
excellent yields. Various functional groups are tolerated.
Z. Liu, R. C. Larock, Org. Lett., 2004, 6, 3739-3741.
A novel and efficient protocol for the rapid construction of dibenzofuran motifs
from 6-diazo-2-cyclohexenones and ortho-haloiodobenzenes involves one-pot
Pd-catalyzed cross-coupling/aromatization and Cu-catalyzed Ullmann coupling.
H. Zhao, K. Yang, H. Zheng, R. Ding, F. Yin, N. Wang, Y. Li, B. Cheng, H. Wang,
H. Zhai, Org. Lett.,
2015,
17, 5744-5747.