21749-83-7Relevant academic research and scientific papers
Palladium-Catalyzed ?±-Arylation of Aryl Acetic Acid Derivatives via Dienolate Intermediates with Aryl Chlorides and Bromides
Sha, Sheng-Chun,Zhang, Jiadi,Walsh, Patrick J.
, p. 410 - 413 (2015)
To date, examples of ?±-arylation of carboxylic acids remain scarce. Using a deprotonative cross-coupling process (DCCP), a method for palladium-catalyzed ?3-arylation of aryl acetic acids with aryl halides has been developed. This protocol is applicable to a wide range of aryl bromides and chlorides. A procedure for the palladium-catalyzed ?±-arylation of styryl acetic acids is also described.
Visible-Light-Driven External-Reductant-Free Cross-Electrophile Couplings of Tetraalkyl Ammonium Salts
Liao, Li-Li,Cao, Guang-Mei,Ye, Jian-Heng,Sun, Guo-Quan,Zhou, Wen-Jun,Gui, Yong-Yuan,Yan, Si-Shun,Shen, Guo,Yu, Da-Gang
, p. 17338 - 17342 (2019/01/04)
Cross-electrophile couplings between two electrophiles are powerful and economic methods to generate C-C bonds in the presence of stoichiometric external reductants. Herein, we report a novel strategy to realize the first external-reductant-free cross-electrophile coupling via visible-light photoredox catalysis. A variety of tetraalkyl ammonium salts, bearing primary, secondary, and tertiary C-N bonds, undergo selective couplings with aldehydes/ketone and CO2. Notably, the in situ generated byproduct, trimethylamine, is efficiently utilized as the electron donor. Moreover, this protocol exhibits mild reaction conditions, low catalyst loading, broad substrate scope, good functional group tolerance, and facile scalability. Mechanistic studies indicate that benzyl radicals and anions might be generated as the key intermediates via photocatalysis, providing a new direction for cross-electrophile couplings.
Ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2
Yan, Si-Shun,Zhu, Lei,Ye, Jian-Heng,Zhang, Zhen,Huang, He,Zeng, Huiying,Li, Chao-Jun,Lan, Yu,Yu, Da-Gang
, p. 4873 - 4878 (2018/06/07)
The first ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2 to generate important aryl acetic acids is reported. Besides aldehyde hydrazones, a variety of ketone hydrazones, which have not been successfully applied in previous umpolung reactions with other reactive electrophiles, also show high reactivity and selectivity under mild conditions. Moreover, this operationally simple protocol features good functional group tolerance, is readily scalable, and offers easy derivation of important structures, including bioactive felbinac and adiphenine. Computational studies reveal that this umpolung reaction proceeds through the generation of a Ru-nitrenoid followed by concerted [4 + 2] cycloaddition with CO2.
Palladium-catalyzed α-arylation of carboxylic acid derivatives with grignard reagent
Tanaka, Daiki,Tanaka, Shota,Mori, Atsunori
supporting information, p. 4254 - 4257 (2014/07/21)
The reaction of arylacetic acid with aryl halides in the presence of a palladium(0) catalyst proceeds with a Grignard reagent (2 equiv.) to afford diarylated acetic acids. Deprotonation was confirmed by treatment with allyl bromide, which revealed that th
Photostimulated reactions of phenylacetic acid dianions with aryl halides. Influence of the metallic cation on the regiochemistry of arylation.
Nwokogu,Wong,Greenwood,Wolfe
, p. 2643 - 2646 (2007/10/03)
[reaction: see text]Phenylacetic acid dianions react via what appears to be an S(RN)1 process with aryl halides under photostimulation to afford aryl substitution products 5 and 6. When the counterion is K+, only 4-biphenylacetic acids 5 are obtained. Both alpha- and para-coupling occurs with Na+ to give a mixture of 5 and 6, while exclusive formation of diphenylacetic acids 6 is observed with the dilithio salt of 1.
Diastereoselectivity in the reduction of sterically unbiased 2,2-diarylcyclopentanones
Halterman, Ronald L.,McEvoy, Marjorie A.
, p. 6690 - 6695 (2007/10/02)
Reduction of sterically unbiased 2-phenyl-2-(4-X-phenyl)cyclopentanones 1 (X = NO2, Br, Cl, OCH3, OH, NH2) with either sodium borohydride in methanol or lithium borohydride in tetrahydrofuran at 0°C produced diastereomeric
