- A direct route to isoflavan quinones. The synthesis of colutequinones A and B
-
The first syntheses of colutequinone A and colutequinone B were achieved. Radical generation via phenyliodoso diacetate was superior to radical generation via ammonium persulfate.
- Kraus, George A.,Kim, Ikyon
-
-
Read Online
- Compound containing carbon-silicon bond and application thereof
-
The invention discloses a compound containing a carbon-silicon bond and application of the compound in construction of the carbon-carbon bond. The invention provides an application of a compound containing the carbon-silicon bond as shown in a formula I or a formula I' in a chemical reaction for constructing the carbon-carbon bond, wherein one carbon in the carbon-carbon bond is from carbon connected with silicon in the compound containing the carbon-silicon bond. According to the preparation method, the compound containing the carbon-silicon bond is used for providing a carbon free radical, and the carbon free radical can directly react with carbon provided in another molecule under a mild condition to construct the carbon-carbon bond; the preparation method is wider in substrate application range, is suitable for functional group activated C and carbon free radical substrates, and is also suitable for unactivated C-H bond substrates.
- -
-
Paragraph 0252-0262
(2020/09/08)
-
- Progress towards metal-free radical alkylations of quinones under mild conditions
-
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
- Galloway, Jordan D.,Baxter, Ryan D.
-
-
- Radical Benzylation of Quinones via C-H Abstraction
-
Herein we report the development of radical benzylation reactions of quinones using Selectfluor and catalytic Ag(I) initiators. The reaction is believed to proceed via a C-H abstraction mechanism after Ag(I)-mediated reduction of Selectfluor. This reaction occurs under mild conditions and is effective for a variety of quinones and radical precursors bearing primary benzylic carbons. The use of preformed Ag(4-OMePy)2NO3 as a catalyst proved effective in improving the reaction efficiency by reducing unwanted degradation pathways available to Selectfluor.
- Galloway, Jordan D.,Mai, Duy N.,Baxter, Ryan D.
-
p. 12131 - 12137
(2019/10/02)
-
- Quinone C-H Alkylations via Oxidative Radical Processes
-
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.
- Hamsath, Akil,Galloway, Jordan D.,Baxter, Ryan D.
-
p. 2915 - 2923
(2018/06/12)
-
- Metal-, Photocatalyst-, and Light-Free, Late-Stage C-H Alkylation of Heteroarenes and 1,4-Quinones Using Carboxylic Acids
-
Contrary to the accepted convention, this work shows that Minisci-type C-H alkylation does not require any metal, photocatalyst, light, or prefunctionalization of the readily available and inexpensive carboxylic acids to proceed well under mild conditions. These mild conditions can be utilized for late-stage alkylations of complex molecules, including pharmaceutical compounds and light-sensitive compounds which degrade under photocatalytic conditions.
- Sutherland, Daniel R.,Veguillas, Marcos,Oates, Conor L.,Lee, Ai-Lan
-
supporting information
p. 6863 - 6867
(2018/11/21)
-
- Naphthoquinone Derivatives, Benzoquinone Derivatives, and Anthracenedione Derivatives, Their Use and Novel Method for Preparation
-
The present invention relates to: a novel manufacturing method of quinone derivatives or anthracenedione derivatives by a copper-catalyzed cross-dehydrogenation coupling reaction of naphthoquinone, benzoquinone or anthracenedione compounds with various cycloalkanes; naphthoquinone derivatives, benzoquinone derivatives and anthracenedione derivatives; and uses thereof. According to the novel manufacturing method of the present invention, since the naphthoquinone derivatives, benzoquinone derivatives or anthracenedione derivatives can be prepared in one step, manufacturing efficiency is improved and cost and time can be saved, and the derivatives according to the present invention can be variously used as an animal medicine.COPYRIGHT KIPO 2019
- -
-
Paragraph 0129-0133; 0148; 0149; 0193; 0194
(2019/02/02)
-
- Silver-Catalyzed Minisci Reactions Using Selectfluor as a Mild Oxidant
-
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.
- Galloway, Jordan D.,Mai, Duy N.,Baxter, Ryan D.
-
supporting information
p. 5772 - 5775
(2017/11/10)
-
- Catalytic asymmetric [2+2] cycloaddition between quinones and fulvenes and a subsequent stereoselective isomerization to 2,3-dihydrobenzofurans
-
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.
- Zheng, Haifeng,Xu, Chaoran,Wang, Yan,Kang, Tengfei,Liu, Xiaohua,Lin, Lili,Feng, Xiaoming
-
supporting information
p. 6585 - 6588
(2017/07/10)
-
- Substituent effects in the oxidation of 2-alkyl-1,4-dialkoxybenzenes with ceric ammonium nitrate
-
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.
- Love, Brian E.,Simmons, Alexander L.
-
p. 5712 - 5715
(2016/11/29)
-
- Ir-catalyzed arylation, alkylation of quinones with boronic acids through C-C coupling
-
Ir-catalyzed arylation, alkylation of quinones with boronic acids was developed under room temperature. Both aryl and alkyl boronic acids are suitable for this transformation. This expands the application scope of the iridium catalyst. This is also an excellent proof that iridium catalysts can be used in the C-C coupling of quinones and naphthoquinones with alkyl boronic acids.
- Wang, Dawei,Ge, Bingyang,Ju, Anqi,Zhou, Yucheng,Xu, Chongying,Ding, Yuqiang
-
supporting information
p. 30 - 33
(2015/01/30)
-
- Copper catalyzed direct alkenylation of simple alkanes with styrenes
-
A novel Cu-catalyzed direct alkenylation of simple alkanes with styrenes was described. In the presence of a catalytic amount of Cu(OTf)2, a diverse range of alkenes undergo coupling with cycloalkanes to produce (E)-alkyl alkenes. This transformation is proposed to proceed via a radical process. This journal is the Partner Organisations 2014.
- Zhu, Yefeng,Wei, Yunyang
-
p. 2379 - 2382
(2014/05/20)
-
- Palladium-catalyzed direct C-H functionalization of benzoquinone
-
A direct Pd-catalyzed C-H functionalization of benzoquinone (BQ) can be controlled to give either mono- or disubstituted BQ, including the installation of two different groups in a one-pot procedure. BQ can now be directly functionalized with aryl, heteroaryl, cycloalkyl, and cyclo-alkene groups and, moreover, the reaction is conducted in environmentally benign water or acetone as solvents.
- Walker, Sarah E.,Jordan-Hore, James A.,Johnson, David G.,MacGregor, Stuart A.,Lee, Ai-Lan
-
supporting information
p. 13876 - 13879
(2015/02/05)
-
- Synthesis of aryl- and alkylquinones through rhodium-catalyzed C-C coupling under mild conditions
-
A direct arylation, alkylation of quinones with aryl and alkyl boronic acids through rhodium-catalyzed C-C coupling has been developed under mild conditions. [CpRhCl2]2 was shown to be the most effective catalyst for the transformation. More importantly, good to excellent yields were obtained under room temperature and base-free conditions. This reaction provides a practical, efficient method for the synthesis of aryl- and alkylquinones.
- Wang, Dawei,Ge, Bingyang,Du, Liyong,Miao, Hongyan,Ding, Yuqiang
-
supporting information
p. 2895 - 2898
(2015/02/02)
-
- Practical C-H functionalization of quinones with boronic acids
-
A direct functionalization of a variety of quinones with several boronic acids has been developed. This scalable reaction proceeds readily at room temperature in an open flask using inexpensive reagents: catalytic silver(I) nitrate in the presence of a persulfate co-oxidant. The scope with respect to quinones is broad, with a variety of alkyl- and arylboronic acids undergoing efficient cross-coupling. The mechanism is presumed to proceed through a nucleophilic radical addition to the quinone with in situ reoxidation of the resulting dihydroquinone. This method has been applied to complex substrates, including a steroid derivative and a farnesyl natural product.
- Fujiwara, Yuta,Domingo, Victoriano,Seiple, Ian B.,Gianatassio, Ryan,Del Bel, Matthew,Baran, Phil S.
-
supporting information; experimental part
p. 3292 - 3295
(2011/05/03)
-
- Modified B-alkylcatecholboranes as radical precursors
-
Generation of radicals from B-alkylcatecholboranes represents an efficient tin-free procedure for the generation of alkyl radicals. A modified version of this method has been developed. The simple catechol is replaced by a dihydroxylated tetrahydroisoquin
- Luethy, Monique,Darmency, Vincent,Renaud, Philippe
-
supporting information; experimental part
p. 547 - 552
(2011/03/22)
-
- Oxidation of phenols with chlorine dioxide
-
The oxidation of different phenols, viz., phenol, 3-methylphenol, 4-methylphenol, 4-tert-butylphenol, 2-cyclohexylphenol, 2,6-di-tert-butyl-4- methylphenol, and 2,4-dichlorophenol, with chlorine dioxide in acetonitrile was studied spectrophotometrically. The reaction rate is described by a second-order equation w = k[PhOH]? [ClO2]. The rate constants were measured and activation parameters of oxidation were determined in a temperature interval of 10-60°C. A dependence of the reaction rate constant on the phenol structure was found. The oxidation products were identified, and their yields were established.
- Ganiev,Ganieva,Kabal'nova
-
p. 2281 - 2284
(2007/10/03)
-
- Electron Paramagnetic Resonance and ENDOR Study of Semiquinones in Reversed Micelles
-
A series of substituted p-benzosemiquinone radical anions have been investigated in reversed micelles by EPR and ENDOR spectroscopies.Compared with EPR studies in homogeneous aqueous phases or in alcoholic solutions, small but significant changes in g val
- Niethammer, Dominique,Kirste, Burkhard,Kurreck, Harry
-
p. 3191 - 3196
(2007/10/02)
-
- THE INVENTION OF RADICAL CHAIN REACTIONS. PART XIV. A DECARBOXILATIVE RADICAL ADDITION TO QUINONES
-
Irradiation of esters 3 derived from aliphatic or alicyclic carboxylic acids and N-hydroxy-2-thiopyridone in the presence of various quinones gives high yields of the corresponding adducts (e.g. 9) with net loss of carbon dioxide.
- Barton, Derek H. R.,Bridon, Dominique,Zard, Samir Z.
-
p. 5307 - 5314
(2007/10/02)
-
- Triphendioxazine dyestuffs
-
Triphendioxazine dyestuffs of the formula STR1 having the substituent meanings specified in the descriptive part, are highly suitable for dyeing and printing hydroxyl- or amido-containing materials, in particular fibre materials, and produce wash-fast dyeings and prints.
- -
-
-