15232-10-7Relevant academic research and scientific papers
Progress towards metal-free radical alkylations of quinones under mild conditions
Galloway, Jordan D.,Baxter, Ryan D.
, (2019)
A new method for the radical alkylation of quinones is reported. Lewis basic nitrogen additives increase the efficacy of quinone alkylations from carboxylic acids using catalytic AgNO3 and Selectfluor as a mild oxidant. Electrochemical data sug
Radical-mediated synthesis of substituted quinones with organotellurium compounds
Yamago, Shigeru,Hashidume, Masahiro,Yoshida, Jun-Ichi
, p. 1234 - 1235 (2000)
Carbon-centered radicals generated from the corresponding organotellurium compounds react with a variety of quinones under photo-thermal conditions to give the monoaddition product in good to excellent yield. The reaction can be used for the synthesis of polyprenyl quinoid natural products.
Quinone C-H Alkylations via Oxidative Radical Processes
Hamsath, Akil,Galloway, Jordan D.,Baxter, Ryan D.
, p. 2915 - 2923 (2018/06/12)
A brief survey of radical additions to quinones is reported. Carboxylic acids, aldehydes, and unprotected amino acids are compared as alkyl radical precursors for the mono- or bis- C-H alkylation of several quinones. Two methods for radical initiation are discussed comparing inorganic persulfates and Selectfluor as stoichiometric oxidants. Kinetic analysis reveals dramatic differences in the rate of radical initiation depending on the identity of the radical precursor and oxidant. Synthetic strategies for efficiently producing alkyl-quinones are discussed in the context of selecting optimum radical precursors and initiators depending on quinone identity and functional groups present.
Silver-Catalyzed Minisci Reactions Using Selectfluor as a Mild Oxidant
Galloway, Jordan D.,Mai, Duy N.,Baxter, Ryan D.
supporting information, p. 5772 - 5775 (2017/11/10)
A new method for silver-catalyzed Minisci reactions using Selectfluor as a mild oxidant is reported. Heteroarenes and quinones both participate in radical C-H alkylation and arylation from a variety of carboxylic and boronic acid radical precursors. Several oxidatively sensitive and highly reactive radical species are successful, providing structures that are challenging to access by other means.
Catalytic asymmetric [2+2] cycloaddition between quinones and fulvenes and a subsequent stereoselective isomerization to 2,3-dihydrobenzofurans
Zheng, Haifeng,Xu, Chaoran,Wang, Yan,Kang, Tengfei,Liu, Xiaohua,Lin, Lili,Feng, Xiaoming
supporting information, p. 6585 - 6588 (2017/07/10)
The catalytic enantioselective [2+2] cycloaddition between quinones and fulvenes was achieved, for the first time, by the use of a chiral copper(ii) complex catalyst. The transformation afforded a series of enantiomerically enriched [6,4,5]-tricyclic cyclobutane derivatives in good yields with excellent regio- and stereoselectivities. Furthermore, the [2+2] adducts could be easily converted into formal [3+2] adducts efficiently and stereoselectively.
Chiral cobalt(II) complex catalyzed Friedel-Crafts aromatization for the synthesis of axially chiral biaryldiols
Xu, Chaoran,Zheng, Haifeng,Hu, Bowen,Liu, Xiaohua,Lin, Lili,Feng, Xiaoming
supporting information, p. 9741 - 9744 (2017/09/07)
An efficient atroposelective synthesis of axially chiral biaryldiols via asymmetric Friedel-Crafts aromatization between p-quinones and 2-naphthols was developed. A chiral cobalt(ii) complex of N,N′-dioxide enabled the process to generate axially chiral biaryldiols in up to 98% yield and 95% ee. A large range of substituents at different positions of p-quinones and 2-naphthols was tolerable. The configuration of the product and the chiral N,N′-dioxide-Co(ClO4)2 catalyst was identified by X-ray crystal diffraction analysis and a possible catalytic model was suggested.
Substituent effects in the oxidation of 2-alkyl-1,4-dialkoxybenzenes with ceric ammonium nitrate
Love, Brian E.,Simmons, Alexander L.
, p. 5712 - 5715 (2016/11/29)
Increased steric size of alkyl groups and the presence of coordinating atoms on alkoxy groups have both been found to contribute to decreasing yields of diquinones upon reaction of 2-alkyl-1,4-dialkoxybenzenes with CAN. The overall hydrophilicity of the substrates does not appear to be a significant factor in determining the diquinone yield for these reactions.
Chemo- and regioselective direct hydroxylation of arenes with hydrogen peroxide catalyzed by a divanadium-substituted phosphotungstate
Kamata, Keigo,Yamaura, Taiyo,Mizuno, Noritaka
supporting information; experimental part, p. 7275 - 7278 (2012/08/28)
Peroxide in, phenol out: The catalyst [-PW10O38V 2(μ-OH)2]3- showed high activity in the hydroxylation of various aromatic compounds with aqueous H2O 2. The system was regioselective, producing para-phenols from monosubstituted benzene derivatives. Furthermore, alkylarenes with reactive side-chain Ca spa 3-H bonds could be chemoselectively hydroxylated without significant formation of side-chain oxygenated products. Copyright
Ruthenium-catalyzed oxidative dearomatization of phenols to 4-(tert-butylperoxy)cyclohexadienones: Synthesis of 2-substituted quinones from p-substituted phenols
Murahashi, Shun-Ichi,Miyaguchi, Noriko,Noda, Shinji,Naota, Takeshi,Fujii, Akiko,Inubushi, Yasutaka,Komiya, Naruyoshi
scheme or table, p. 5355 - 5365 (2011/11/14)
The ruthenium-catalyzed oxidation of phenols with tert-butylhydroperoxide efficiently gives the corresponding 4-(tert-butylperoxy)cyclohexadienones. The oxidation proceeds selectively because of ruthenium's ability for rapid single-electron transfer. This biomimetic oxidation reaction is highly useful to obtain the metabolic compounds desired for confirming the safety of medicines and related compounds. Typically, the first metabolic compound of the female hormone estrone is readily obtained by this biomimetic oxidation reaction. The resulting 4-(tert-butylperoxy)cyclohexadienones are versatile synthetic intermediates, which can be transformed into 2-substituted 1,4-benzoquinones by treatment with acid catalysts. Acid-promoted rearrangement followed by a Diels-Alder reaction provides a new strategy for the synthesis of fused cyclic compounds, such as naphthoquinone and anthraquinone derivatives, from readily available phenols. The nonnatural 1,4-diacetoxy steroidal skeleton is obtained by the oxidation of estrone followed by zinc-mediated migration. Vitamin K 3 is synthesized selectively from p-cresol in an overall 79 % yield in 4 steps, and the synthesis includes the ruthenium-catalyzed oxidation.
Synthesis of 2-substituted quinones, vitamin K3, and vitamin K1 from p-cresol. BF3·OEt2-catalyzed methyl migration of 4-tert-butyldioxycyclohexadienones
Murahashi, Shun-Ichi,Fujii, Akiko,Inubushi, Yasutaka,Komiya, Naruyoshi
scheme or table, p. 2339 - 2341 (2010/05/19)
BF3·OEt2-catalyzed methyl group migration of 4-methyl-4-tert-butyldioxycyclohexadienone, which is obtained by ruthenium-catalyzed oxidation of p-cresol with tert-butyl hydroperoxide, in hexafluoro-2-propanol/toluene gave toluquinone efficiently. The reaction can be applied to the regio-selective short-step syntheses of vitamin K3 and vitamin K1 from p-cresol.
