17735-20-5Relevant academic research and scientific papers
Metal triflates-methanesulfonic acid as new catalytic systems: Application to the Fries rearrangement
Mouhtady, Omar,Gaspard-Iloughmane, Hafida,Roques, Nicolas,Le Roux, Christophe
, p. 6379 - 6382 (2003)
A surprising synergistic effect has been discovered between metal triflates (Mg, Ca, Sc, Cu, Zn, Y, Ln, Bi) and methanesulfonic acid, leading to active catalytic systems for the Fries rearrangement. In particular, the systems based on yttrium and copper(II) triflate proved to be very active and much cheaper than scandium triflate. The efficiency of these systems might result from the catalytic Lewis acid activation of Br?nsted acids.
The Catalytic Fries Rearrangement of Acyloxy Naphthalenes using Scandium Trifluoromethanesulfonate as a Castalyst
Kobayashi, Shu,Moriwaki, Mitsuhiro,Hachiya, Iwao
, p. 1527 - 1528 (1995)
The catalytic Fries rearrangement of acyloxy naphthalenes proceeds smoothly using a small amount of scandium trifluoromethanesulfonate (5 molpercent) to afford the corresponding hydroxynaphthyl ketones in high yields.
Synthesis of 2-acylphenol and flavene derivatives from the ruthenium-catalyzed oxidative c-h acylation of phenols with aldehydes
Lee, Hanbin,Yi, Chae S.
supporting information, p. 1899 - 1904 (2015/03/18)
The cationic ruthenium hydride complex [(C6H6)(PCy3)(CO)RuH]+BF4- has been found to be an effective catalyst for the oxidative C-H coupling reaction of phenols with aldehydes to give 2-acylphenol compounds. The coupling of phenols with α,β-unsaturated aldehydes selectively gives the flavene derivatives. The catalytic method mediates direct oxidative C-H coupling of phenol and aldehyde substrates without using any metal oxidants or forming wasteful byproducts. A cationic ruthenium hydride complex catalyzes the oxidative C-H coupling of phenols with aldehydes to form 2-acylphenol and flavene derivatives.
Improvement of Selectivity in the Fries Rearrangement and Direct Acylation Reactions by Means of P2O5/SiO2 Under Microwave Irradiation in Solvent-Free Media
Eshghi, Hossein,Rafie, Mohammad,Gordi, Zinat,Bohloli, Moosa
, p. 1258 - 1270 (2007/10/03)
P2O5/SiO2 was found to be an efficient new reagent for the Fries rearrangement of acyloxy benzene or naphthalene derivatives and the direct acylation reactions of phenol and naphthol derivatives with carboxylic acids. The reactions proceeded smoothly in the solid state and are highly selective methods for the preparation of the ortho isomers of hydroxyaryl ketones. Microwave irradiation improved the conversion yield to 85-100 percent and the high ortho-regioselectivity of these reactions provides an efficient and versatile procedure for obtaining o-hydroxyaryl ketones in 47-98 percent yield.
The Catalytic Fries Rearrangement and o-Acylation Reactions Using Group 3 and 4 Metal Triflates as Catalysts
Kobayashi, Shue,Moriwaki, Mitsuhiro,Hachiya, Iwao
, p. 267 - 273 (2007/10/03)
Group 3 and 4 metal triflates (Sc(OTf)3, TiCl(OTf)3, Zr(OTf)4, and Hf(OTf)4) were found to be efficient catalysts in the Fries rearrangement of phenyl or 1 -naphthyl acylates. It was also found that the o-acylation (direct acylation) reactions of phenols and 1-naphthols with acid chlorides proceeded smoothly in the presence of the triflates. Both reactions were successfully carried out using small amounts of the triflates (catalytically), and comparison of catalytic activities of these metal triflates in these reactions is discussed.
Hafnium trifluoromethanesulfonate (Hf(OTf)4) as an efficient catalyst in the Fries rearrangement and direct acylation of phenol and naphthol derivatives
Kobayashi, Shue,Moriwaki, Mitsuhiro,Hachiya, Iwao
, p. 2053 - 2056 (2007/10/03)
Hafnium trifluoromethanesulfonate (hafnium triflate, Hf(OTf)4) was found to be an efficient catalyst in the Fries rearrangement of acyloxy benzene or naphthalene derivatives. The reactions proceeded smoothly in the presence of 5-20 mol% Hf(OTf)4. Regioselective direct acylation of phenol and naphthol derivatives with acid chlorides was also achieved by using Hf(OTf)4 as a catalyst.
Rare Earth Metal Complexes as Water-Tolerant Lewis Acid Catalysts in Organic Synthesis
Kobayashi,Hashiya,Ishitani,Moriwaki,Nagayama
, p. 193 - 202 (2007/10/03)
Rare earth metal triflates are stable in aqueous media and can act as Lewis acid catalysts in several carbon-carbon bond forming reactions. This article describes some of these reactions; aldol and Mannich-type reactions in aqueous solution, and Friedel-Crafts acylations and Fries rearrangement in organic solvents. The reactions proceeded smoothly in the presence of a catalytic amount of the triflate under mild conditions. Moreover, the catalysts could be recovered after the reactions were completed and could be reused.
PHOTO FRIES REARRANGEMENTS OF 1-NAPHTHYL ESTERS IN THE SYNTHESIS OF 2-ACYLNAPHTHOQUINONES
Crouse, David J.,Hurlbut, Sheri L.,Wheeler, Desmond M.S.
, p. 374 - 378 (2007/10/02)
The photo Fries rearrangements of esters of 1-naphthol and 5-methoxy-1-naphthol to the corresponding 1-hydroxy-2-acylnaphthalenes have been carried out.The best yield (70percent) was obtained by irradiating 5-methoxy-1-naphthyl acetate in ethyl acetate.By contrast the yield from 1-naphthyl acetate under similar conditions was 40percent.Oxidation of 1-hydroxy-5-methoxy-2-naphthyl cyclohexyl ketone with thallium trinitrate gave the corresponding 1,4-quinone.These results provide a method for the regioselective synthesis of tricyclic analogues of adriamycinone.
