64701-03-7Relevant academic research and scientific papers
Synthesis of (+)-Antroquinonol and Analogues by Using Enantioselective Michael Reactions of Benzoquinone Monoketals
Hsu, Che-Sheng,Fang, Jim-Min
, p. 3809 - 3816 (2016/08/16)
(+)-Antroquinonol is an anticancer agent that was first isolated from the rare mushroom Antrodia cinnamomea, which is indigenous to Taiwan. In this study, (+)-antroquinonol is synthesized from benzoquinone monoketals by using an enantioselective Michael r
Unanticipated participation of HCl in nucleophilic chlorination reaction: Expedient route to meta chlorophenols
Chittimalla, Santhosh Kumar,Bandi, Chennakesavulu
supporting information, p. 15 - 19 (2015/12/23)
o-Quinone monoketals participated in a 1,4-addition reaction with HCl furnishing m-chlorophenols in high yields. Several readily available o-quinone monoketals were selected to display the generality of this serendipitous and unprecedented reaction and the results are presented herein.
Efficient Coupling Reaction of Quinone Monoacetal with Phenols Leading to Phenol Biaryls
Kamitanaka, Tohru,Morimoto, Koji,Tsuboshima, Kohei,Koseki, Daichi,Takamuro, Hitoho,Dohi, Toshifumi,Kita, Yasuyuki
supporting information, p. 15535 - 15538 (2016/12/09)
A simple and efficient synthesis of phenol biaryls by the cross-couplings of quinone monoacetals (QMAs) and phenols is reported. The Br?nsted acid catalytic system in 1,1,1,3,3,3-hexafluoro-2-propanol was found to be particularly efficient for this transformation. This reaction can be extended to the synthesis of various phenol biaryls, including sterically hindered biaryls, with yields ranging from 58 to 90 % under mild reaction conditions and in a highly regiospecific manner.
Synthesis of o-chlorophenols via an unexpected nucleophilic chlorination of quinone monoketals mediated by N,N′-dimethylhydrazine dihydrochloride
Yin, Zhiwei,Zhang, Jinzhu,Wu, Jing,Green, Riana,Li, Sihan,Zheng, Shengping
supporting information, p. 2854 - 2858 (2014/05/06)
An unexpected nucleophilic chlorination of a quinone monoketal while carrying out a pyrazolidine synthesis has led to a general preparation of multisubstituted phenols. The products are obtained in good to high yields under mild conditions. The bridged pyrazolidines that were the original targets are obtained in the presence of a protic solvent. This journal is the Partner Organisations 2014.
Br?nsted acid-controlled [3 + 2] coupling reaction of quinone monoacetals with alkene nucleophiles: A catalytic system of perfluorinated acids and hydrogen bond donor for the construction of benzofurans
Hu, Yinjun,Kamitanaka, Tohru,Mishima, Yusuke,Dohi, Toshifumi,Kita, Yasuyuki
, p. 5530 - 5543 (2013/07/26)
We have developed an efficient Br?nsted acid-controlled strategy for the [3 + 2] coupling reaction of quinone monoacetals (QMAs) with nucleophilic alkenes, which is triggered by the particular use of a specific acid promoter, perfluorinated acid, and a solvent, fluoroalcohol. This new coupling reaction smoothly proceeded with high regiospecificity in regard with QMAs for introducing π-nucleophiles to only the carbon α to the carbonyl group, thereby providing diverse dihydrobenzofurans and derivatives with high yields, up to quantitative, under mild conditions in short reaction times. The choice of Br?nsted acid enabled us to avoid hydrolysis of the QMAs, which gives quinones, and the formation of discrete cationic species from the QMAs. Notably, further investigations in this study with regard to the acid have led to the findings that the originally stoichiometrically used acid could be reduced to a catalytic amount of 5 mol % loading or less and that the stoichiometry of the alkenes could be significantly improved down to only 1.2 equiv. The facts that only a minimal loading (5 mol %) of perfluoroterephthalic acid is required, readily available substrates can be used, and the regioselectivity can be controlled by the acid used make this coupling reaction very fascinating from a practical viewpoint.
Hypervalent iodine mediated synthesis of carbamate protected p-quinone monoimine ketals and p-benzoquinone monoketals
Bodipati, Naganjaneyulu,Peddinti, Rama Krishna
experimental part, p. 4549 - 4553 (2012/07/14)
A simple and efficient method for the synthesis of p-quinone monoimide ketals and p-benzoquinone monoketals by using a hypervalent iodine reagent, diacetoxyiodobenzene, has been developed. These two types of ketals are achieved from a single starting material by varying the reaction conditions.
Tin tetrachloride-catalyzed regiospecific allylic substitution of quinone monoketals: An easy entry to benzofurans and coumestans
Liu, Yingjie,Liu, Jingxin,Wang, Mang,Liu, Jun,Liu, Qun
supporting information, p. 2678 - 2682 (2013/01/15)
A highly regioselective allylic substitution of quinone monoketals with a-oxoketene dithioacetals is achieved under the catalysis of only tin tetrachloride (1 mol%). The advantages of the reaction, including its simplicity, rapidity, low catalyst loading of inexpensive tin tetrachloride, mild conditions and; in particular, the regiospecificity, is proposed to be due to a pseudo-intramolecular process. This new synthetic method provides a facile [3+2] cycloaddition route to benzofurans and is highlighted by the synthesis of coumestans.
Efficient synthesis of oxygenated terphenyls and other oligomers: Sequential arylation reactions through phenol oxidation-rearomatization
Dohi, Toshifumi,Kamitanaka, Tohru,Watanabe, Shohei,Hu, Yinjun,Washimi, Naohiko,Kita, Yasuyuki
supporting information, p. 13614 - 13618 (2013/01/15)
One by one: Starting from simple phenols, a diverse series of oxygenated terphenyl compounds can be prepared in a concise and practical manner using sequential arylation reactions involving phenol oxidation/rearomatization and quinone monoacetal intermediates (see scheme). Many of the terphenyl products can be used for preparing well-defined oligomers and, furthermore, contain valuable functional groups that can be transformed for further diversification. Copyright
[3 + 2] coupling of quinone monoacetals by combined acid-hydrogen bond donor
Dohi, Toshifumi,Hu, Yinjun,Kamitanaka, Tohru,Washimi, Naohiko,Kita, Yasuyuki
supporting information; experimental part, p. 4814 - 4817 (2011/11/13)
The expeditious and efficient [3 + 2] coupling approach of quinone monoacetals 1 with alkene nucleophiles 2 by the action of an activated Bronsted acid in the presence of a hydrogen bond donor perfluorinated alcohol has been achieved. With the optimized combined acid, the reaction could proceed under mild conditions by only mixing the two reactants to afford the cycloadducts 3 in a short time (within 10 min) with good to quantitative yields.
Reaction discovery using microfluidic-based multidimensional screening of polycyclic Iminium Ethers
Treece, Jennifer L.,Goodell, John R.,Velde, David Vander,Porco Jr., John A.,Aube, Jeffrey
supporting information; experimental part, p. 2028 - 2038 (2010/06/20)
"Chemical Equation Presented" Polycyclic iminium ethers are ambident electrophilic intermediates that react with a range of nucleophiles in a highly condition-dependent manner to afford densely functionalized lactams. In an effort to expand the scope of reactivity and assist in the generation of new chemotypes from these intermediates, several iminium, ethers were subjected to reaction screening using an automated microfluidics reaction platform. Application of this approach led to the discovery of several interesting reaction pathways involving the iminium ether intermediates that, will be described.
