607-88-5Relevant academic research and scientific papers
Synthesis of salicylates from anionically activated aromatic trifluoromethyl group
Lin, Chuankai,Liu, Jin-Biao,Wang, Ruixiang,Xie, Huilin
supporting information, (2021/12/22)
An efficient approach to salicylates via a novel transformation of anionically activated aromatic trifluoromethyl group is described. Anionically activated trifluoromethyl group can react with phenols/alcohols under alkaline conditions to afford aryl/alkyl salicylates in high yields. Mechanism studies indicate that the carbonyl oxygen atom of ester is from the H2O in the solvent.
Cerium photocatalyzed radical smiles rearrangement of 2-aryloxybenzoic acids
Tripathy, Alisha Rani,Yatham, Veera Reddy,Yedase, Girish Suresh
, p. 25207 - 25210 (2021/08/05)
We report herein a cerium photocatalyzed aryl migration from an aryl ether to a carboxylic acid group through radical-Smiles rearrangement. This operationally simple protocol utilizes inexpensive CeCl3as a photocatalyst and converted a variety of 2-aryloxybenzoic acids into aryl-2-hydroxybenzoates in good yields.
N-Heterocyclic carbene/photo-cocatalyzed oxidative Smiles rearrangement: Synthesis of aryl salicylates from: O -aryl salicylaldehydes
Xia, Zi-Hao,Dai, Lei,Gao, Zhong-Hua,Ye, Song
supporting information, p. 1525 - 1528 (2020/02/13)
The N-heterocyclic carbene/photo-cocatalyzed oxidative Smiles rearrangement of O-aryl salicylaldehydes was developed. Both electron-deficient and electron-rich aryls worked well as migrating groups, giving the corresponding aryl salicylates in good yields. This reaction features formation of two new C-O bonds and one C-O bond cleavage via metal-free oxidation of the Breslow intermediate using oxygen as the terminal oxidant and following the Smiles rearrangement under photocatalysis.
A photoredox-neutral Smiles rearrangement of 2-aryloxybenzoic acids
Gonzalez-Gomez, Jose C.,Ramirez, Nieves P.,Lana-Villarreal, Teresa,Bonete, Pedro
, p. 9680 - 9684 (2017/11/30)
We report on the use of visible light photoredox catalysis for the radical Smiles rearrangement of 2-aryloxybenzoic acids to obtain aryl salicylates. The method is free of noble metals and operationally simple and the reaction can be run under mild batch or flow conditions. Being a redox neutral process, no stoichiometric oxidants or reductants are needed.
Efficient Aryl Migration from an Aryl Ether to a Carboxylic Acid Group To Form an Ester by Visible-Light Photoredox Catalysis
Wang, Shao-Feng,Cao, Xiao-Ping,Li, Yang
, p. 13809 - 13813 (2017/10/24)
We have developed a highly efficient aryl migration from an aryl ether to a carboxylic acid group through retro-Smiles rearrangement by visible-light photoredox catalysis at ambient temperature. Transition metals and a stoichiometric oxidant and base are avoided in the transformation. Inspired by the high efficiency of this transformation and the fundamental importance of C?O bond cleavage, we developed a novel approach to the C?O cleavage of a biaryl ether to form two phenolic compounds, as demonstrated by a one-pot, two-step gram-scale reaction under mild conditions. The aryl migration exhibits broad scope and can be applied to the synthesis of pharmaceutical compounds, such as guacetisal. Primary mechanistic studies indicate that the catalytic cycle occurs by a reductive quenching pathway.
Carboxyl radical-assisted 1,5-aryl migration through Smiles rearrangement
Hossian, Asik,Jana, Ranjan
supporting information, p. 9768 - 9779 (2016/10/31)
We report herein, a silver(i)-catalyzed Smiles rearrangement of 2-aryloxy- or 2-(arylthio)benzoic acids to provide aryl-2-hydroxybenzoate or aryl-2-mercaptobenzoate dimer, respectively, through 1,5-aryl migration from oxygen or sulfur to carboxylate oxygen. Mechanistically, the aryl ether moiety undergoes an intramolecular ipso attack by the carboxyl radical followed by a C-O or C-S bond cleavage. Aryl-2-mercaptobenzoates undergo oxidative dimerization through a thiol moiety in situ.
Formation of dibenzofurans by flash vacuum pyrolysis of aryl 2-(allyloxy)benzoates and related reactions
Black, Michael,Cadogan,McNab, Hamish
experimental part, p. 2961 - 2967 (2010/09/06)
Flash vacuum pyrolysis (FVP) of aryl 2-(allyloxy)benzoates 5 and of the corresponding aryl 2-(allylthio)benzoates 6 at 650°C, gives dibenzofurans 19 and dibenzothiophenes 20, respectively. The mechanism involves generation of phenoxyl (or thiophenoxyl) radicals by homolysis of the O-allyl (or S-allyl) bond, followed by ipso attack at the ester group, loss of CO2 and cyclisation of the resulting aryl radical. Synthetically, the procedure works well for p-substituted substrates, which lead to 2-substituted dibenzofurans 19b-f (73-90%) and dibenzothiophenes 20b-c (90-94%). Little selectivity is shown in the cyclisation of m-substituted substrates and competing interactions of the radical with the substituent - and ipso-attack - complicate the pyrolyses of o-substituted substrates. FVP of related radical precursors including 2-(allyloxy)phenyl benzoates 43 gave no dibenzofurans, whereas 2-(allyloxy-5-methyl)azobenzene 44 gave a much reduced yield. No carbazoles were obtained by FVP of 4-methylphenyl 2-(allylamino)benzoate 42.
