4919-96-4Relevant articles and documents
Ligand- and Counterion-Assisted Phenol O-Arylation with TMP-Iodonium(III) Acetates
Kikushima, Kotaro,Miyamoto, Naoki,Watanabe, Kazuma,Koseki, Daichi,Kita, Yasuyuki,Dohi, Toshifumi
supporting information, p. 1924 - 1928 (2022/03/27)
High reactivity of trimethoxyphenyl (TMP)-iodonium(III) acetate for phenol O-arylation was achieved. It was first determined that the TMP ligand and acetate anion cooperatively enhance the electrophilic reactivity toward phenol oxygen atoms. The proposed method provides access to various diaryl ethers in significantly higher yields than the previously reported techniques. Various functional groups, including aliphatic alcohol, boronic ester, and sterically hindered groups, were tolerated during O-arylation, verifying the applicability of this ligand- and counterion-assisted strategy.
Sulphonic acid functionalized porphyrin anchored with a: Meso -substituted triazolium ionic liquid moiety: A heterogeneous photo-catalyst for metal/base free C-C cross-coupling and C-N/C-H activation using aryl chloride under visible light irradiation
Bhansali, Karan,Raut, Subodh,Barange, Shital,Bhagat, Pundlik
, p. 19690 - 19712 (2020/12/04)
We report an easy process to synthesize sulphonic acid functionalized porphyrin, anchored with a meso-substituted triazolium ionic liquid moiety (SAFPTILM) for metal/base free C-C cross-coupling and C-N/C-H activation using aryl chloride under visible light irradiation. The acid strength has been measured based on the Hammett indicator. The SAFPTILM photocatalyst comprising 18 π-conjugated electronic systems with the chromophore substituents in the meso-position can provide rapid electronic conducting channels during photocatalysis under the irradiation of visible light. It was found that SAFPTILM is an efficient photocatalyst for the Heck, Sonogashira, Buchwald, Ullmann/Fittig coupling and C-H activation of phenols with different aryl chlorides in the absence of a base/noble metal, using 5 W LED (yellow) light under ambient conditions. The photocatalyst with low band gap (1.55 eV) comprising conjugation, favors coupling reaction of unactivated aryl chlorides, by easy excitation of electrons and transfer to the conjugated benzimidazolium based phenylenediamine support delaying the recombination of photoinduced electron-hole pairs.
Site-selective Oxidative Dearomatization of Phenols and Naphthols into ortho-Quinols or Epoxy ortho-Quinols using Oxone as the Source of Dimethyldioxirane
Cabrera-Afonso, María J.,Carre?o, M. Carmen,Urbano, Antonio
supporting information, (2019/08/21)
A novel reactivity of dimethyldioxirane, generated in situ from Oxone and acetone, with substituted phenols and naphthols is reported. This methodology allowed the synthesis of ortho-quinols or epoxy ortho-quinols from a site-selective oxidative dearomatization process, with good yields under very mild conditions. A short total synthesis of natural product lacinilene C methyl ether is also described using this process as the key step. (Figure presented.).
