294863-12-0Relevant academic research and scientific papers
Scope and mechanism of the PdII-catalyzed arylation/carboalkoxylation of unactivated olefins with indoles
Liu, Cong,Widenhoefer, Ross A.
, p. 2371 - 2382 (2006)
Treatment of 1-methyl-2-(4-pentenyl)indole (5) with a catalytic amount of [PdCl2(MeCN)2] (2: 5 mol%) and a stoichiometric amount of CuCl2 (3 equiv) in methanol under CO (1 atm) at room temperature for 30 min gives methyl (9-methyl-2,3,4,9-tetrahydro-4-carhazolyl)acetale (6). which was isolated in 83% yield. A number of 2- and 3-alkenyl indoles undergo a similar palladium-catalyzed cyclization/carhoalkoxylation to give the corresponding polycyclic indole derivatives in moderate to excellent yields with excellent regio- and diaste reoselectivity. Under similar conditions, vinyl arenes undergo intermolecular arylation/carhoalkoxylation with indoles to give 3-(1-aryl-2-carbomethoxyethyl) indoles in moderate yield with high regioselectivity. Stereochemical analyses of the palladium-catalyzed cyclization/ carboalkoxylation of both 2- and 3-alkenyl indoles are in agreement with mechanisms involving outer-sphere attack of the indole on a palladiumolefin complex followed by α-migratory insertion of CO and methanolysis of the resulting acyl palladium intermediate. CuCl2 functions as the terminal oxidant in this palladium-catalyzed cyclization/carboalkoxylation of alkenyl indoles and also significantly increases the rate of reaction of 2 with the alkenyl indole to form the corresponding acyl palladium complex. Spectroscopic studies are in agreement with the intermediacy of a heterobimetallic Pd/Cu complex as the active catalyst in this reaction.
Palladium-catalyzed cyclization/carboalkoxylation of alkenyl indoles
Liu, Cong,Widenhoefer, Ross A.
, p. 10250 - 10251 (2004)
Reaction of 1-methyl-2-(4-pentenyl)indole with a catalytic amount of PdCl2(CH3CN)2 (5 mol %) and a stoichiometric amount of CuCl2 (3 equiv) in methanol under CO (1 atm) at room temperature for 30 min led to cyclization/carboalkoxylation to form the corresponding tetrahydrocarbazole in 83% isolated yield as a single regioisomer. Palladium-catalyzed cyclization/carboalkoxylation of 2-(4-pentenyl)indoles tolerated substitution along the alkenyl chain and at the internal and cis-terminal olefinic positions. Palladium-catalyzed cyclization/carboalkoxylation tolerated a range of alcohols and was effective for the cyclization of 2-(3-butenyl)indoles, 3-(3-butenyl)indoles, 3-(4-pentenyl)indoles, and 2-(5-hexenyl)indoles. Copyright
Synthesis of Enantioenriched Indolines by a Conjugate Addition/Asymmetric Protonation/Aza-Prins Cascade Reaction
Daniels, Blake E.,Ni, Jane,Reisman, Sarah E.
, p. 3398 - 3402 (2016)
A conjugate addition/asymmetric protonation/aza-Prins cascade reaction has been developed for the enantioselective synthesis of fused polycyclic indolines. A catalyst system generated from ZrCl4 and 3,3′-dibromo-BINOL enables the synthesis of a range of polycyclic indolines in good yields and with high enantioselectivity. A key finding is the use of TMSCl and 2,6-dibromophenol as a stoichiometric source of HCl to facilitate catalyst turnover. This transformation is the first in which a ZrCl4BINOL complex serves as a chiral Lewis-acid-assisted Br?nsted acid.
Olefination via Cu-Mediated Dehydroacylation of Unstrained Ketones
Dong, Guangbin,Xu, Yan,Zhou, Xukai
supporting information, p. 20042 - 20048 (2021/12/03)
The dehydroacylation of ketones to olefins is realized under mild conditions, which exhibits a unique reaction pathway involving aromatization-driven C-C cleavage to remove the acyl moiety, followed by Cu-mediated oxidative elimination to form an alkene between the α and β carbons. The newly adopted N′-methylpicolinohydrazonamide (MPHA) reagent is key to enable efficient cleavage of ketone C-C bonds at room temperature. Diverse alkyl- and aryl-substituted olefins, dienes, and special alkenes are generated with broad functional group tolerance. Strategic applications of this method are also demonstrated.
Highly efficient construction of benzene ring in carbazoles by palladium-catalyzed endo-mode oxidative cyclization of 3-(3′-alkenyl) indoles
Kong, Aidi,Han, Xiuling,Lu, Xiyan
, p. 1339 - 1342 (2007/10/03)
A highly efficient construction of the benzene ring in carbazoles by palladium-catalyzed endo-mode oxidative cyclization of 3-(3′-alkenyl)- indoles was developed. The reaction utilizes benzoquinone as the stoichiometric oxidant and is conducted under mild conditions.
Heterocyclic compound, composition and method for inhibiting adenosine deaminase
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, (2008/06/13)
Heterocyclic compounds of the following formula: wherein B is ?[wherein R1is hydrogen or lower alkyl; R2is hydrogen or lower alkyl; and X is hydrogen or hydroxy protective group], lower alkanoyl or hydroxyimino(lower)alkyl A is lower
