41389-12-2Relevant academic research and scientific papers
Investigating the microwave-accelerated Claisen rearrangement of allyl aryl ethers: Scope of the catalysts, solvents, temperatures, and substrates
Hui, Zi,Jiang, Songwei,Qi, Xiang,Ye, Xiang-Yang,Xie, Tian
supporting information, (2020/05/18)
The microwave-accelerated Claisen rearrangement of allyl aryl ethers was investigated, in order to gain insight into the scope of the catalysts, solvents, temperatures, and substrates. Among the catalysts examined, phosphomolybdic acid (PMA) was found to greatly accelerate the reaction in NMP, at temperatures ranging from 220 to 300 °C. This method was found to be useful for preparing several intermediates previously reported in the literature using precious metal catalysts such as Au(I), Ag(I), and Pt(II). Additionally, substrates bearing bromo and nitro groups on the aryl portion required careful tailoring of the reaction conditions to avoid complex product profiles.
Microwave-assisted zeolite catalyzed claisen rearrangement of allyl aryl ethers under solvent-free conditions
Deodhar, Deepak K.,Tipnis, Amol S.,Samant, Shriniwas D
experimental part, p. 1552 - 1555 (2011/02/23)
Claisen rearrangement of allyl aryl ethers has been studied extensively over various zeolites under microwave activation and solvent free conditions at 80°C. Hβ-zeolite is found to be an efficient catalyst for the rearrangement. The reaction gives ω-rearranged product selectively instead of expected further cyclized dihydrobenzofuran derivative.
Microwave-accelerated Claisen rearrangement in bicyclic imidazolium [b-3C-im][NTf2] ionic liquid
Lin, Yung-Lun,Cheng, Jen-Yen,Chu, Yen-Ho
, p. 10949 - 10957 (2008/02/13)
With microwaves, a chemically stable ionic liquid [b-3C-im][NTf2] recently developed in our laboratory was used as solvent and successfully applied to accelerate Claisen rearrangement reactions at high temperatures. In the presence of Lewis acid MgCl2, these thermal rearrangements could be achieved in similar reaction times but at lower temperature. For the microwaved reactions studied in this work, without scarifying isolated yields, the reaction times were significantly reduced from hours (by conventional heating) to ≤3 min. Our result also demonstrated that [b-3C-im][NTf2] ionic liquid was a useful solvent substitute and could be recycled multiple times for the studied rearrangement reaction at elevated temperatures.
Using geminal dicationic ionic liquids as solvents for high-temperature organic reactions
Han, Xinxin,Armstrong, Daniel W.
, p. 4205 - 4208 (2007/10/03)
(Chemical Equation Presented) Several organic reactions conducted at high temperatures, including the isomerization reaction, the Claisen rearrangement, and the Diels-Alder reaction, were investigated in three geminal dicationic ionic liquids with high thermal stability. High to moderate yields of the products for most entries were obtained. Advantages of these approaches are discussed. These ionic liquids were shown to be recyclable. The utility of these ionic liquid solvents for high-temperature organic reactions was demonstrated.
Regioselectivity in aromatic Claisen rearrangements
Gozzo, Fabio Cesar,Fernandes, Sergio Antonio,Rodrigues, Denise Cristina,Eberlin, Marcos Nogueira,Marsaioli, Anita Jocelyne
, p. 5493 - 5499 (2007/10/03)
Theoretical calculations and the isomeric product composition for a series of eight meta-substituted allyl aryl ethers confirm the reliability of a new 1H NMR methodology used to predict aromatic Claisen regioselectivity from ground-state confo
Claisen Rearrangement of meta-Substituted Allyl Phenyl Ethers
Bruce, J. Malcolm,Roshan-Ali, Yusuf
, p. 2677 - 2679 (2007/10/02)
Electron-releasing substituents at the 3-position of allyl phenyl ethers favour Claisen rearangement of the allyl group to the 6-position, whereas electron-acceptors favour migration to the 2-position. 2-Acylhydroquinone 4-allyl ethers yield, predominantly, the 3-allyl isomers, probably because internal hydrogen bonding confers naphthalenoid character on the aryl residue.
