55682-11-6Relevant articles and documents
Semi-heterogeneous Dual Nickel/Photocatalysis using Carbon Nitrides: Esterification of Carboxylic Acids with Aryl Halides
Pieber, Bartholom?us,Malik, Jamal A.,Cavedon, Cristian,Gisbertz, Sebastian,Savateev, Aleksandr,Cruz, Daniel,Heil, Tobias,Zhang, Guigang,Seeberger, Peter H.
supporting information, p. 9575 - 9580 (2019/06/25)
Cross-coupling reactions mediated by dual nickel/photocatalysis are synthetically attractive but rely mainly on expensive, non-recyclable noble-metal complexes as photocatalysts. Heterogeneous semiconductors, which are commonly used for artificial photosynthesis and wastewater treatment, are a sustainable alternative. Graphitic carbon nitrides, a class of metal-free polymers that can be easily prepared from bulk chemicals, are heterogeneous semiconductors with high potential for photocatalytic organic transformations. Here, we demonstrate that graphitic carbon nitrides in combination with nickel catalysis can induce selective C?O cross-couplings of carboxylic acids with aryl halides, yielding the respective aryl esters in excellent yield and selectivity. The heterogeneous organic photocatalyst exhibits a broad substrate scope, is able to harvest green light, and can be recycled multiple times. In situ FTIR was used to track the reaction progress to study this transformation at different irradiation wavelengths and reaction scales.
Palladium(II)-catalyzed direct conversion of methyl arenes into aromatic nitriles
Shu, Zhibin,Ye, Yuxuan,Deng, Yifan,Zhang, Yan,Wang, Jianbo
supporting information, p. 10573 - 10576 (2013/10/21)
From methyl to nitrile: A mild ammoxidation method, which directly converts methyl arenes into aromatic nitriles, has been developed by using Pd(OAc) 2 and N-hydroxyphthalimide (NHPI) as the catalysts, and tert-butyl nitrite as the nitrogen source and oxidant. Copyright
SPIROKETONE ACETYL-COA CARBOXYLASE INHIBITORS
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Page/Page column 25-26, (2008/12/06)
The invention provides compounds of Formula (1) or a pharmaceutically acceptable salt of said compound, wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are as described herein; pharmaceutical compositions thereof; and the use thereof in treating mammals suffering from the condition of being overweight.
Transfer of a positively charged acyl group between substituted phenolate ion nucleophiles: The Bronsted β for the calibrating equilibrium for N-methylisonicotinyl (4-carbonyl-N-methylpyridinium) transfer
Colthurst, Matthew J.,Nanni, Matilde,Williams, Andrew
, p. 2285 - 2291 (2007/10/03)
Rate constants have been measured for the reaction of substituted phenolate ions with aryl acetate esters and with aryl N-methylisonicotinate esters? in aqueous solution. A new method is demonstrated for determining βeq for group transfer from 4-nitrophenyl esters; it employs the rate constant for the reaction of 2,6-difluorophenolate ion with substituted phenyl ester as a surrogate for the reactivity of the 4-nitrophenolate ion and yields βeq = 1.55 for the N-methylisonicotinyl transfer reaction. The Bronsted-type plot of the rate constant for phenolate ion attack on 4-nitrophenyl N-methylisonicotinate is linear over a range of pKa values from 5.5 to 10 and provides good evidence for a concerted displacement mechanism for this reaction. The reactivity of the N-methylisonicorinate esters to phenolate ions is some 300 times larger than that of the corresponding acetate esters but the larger βnuc value (0.90 compared with 0.74) suggests a 'later' transition structure. Calibration of the β values with the corresponding βeq gives a Leffler αnuc = 0.58 and 0.42 for N-methylisonicotinate and acetate respectively, which contrasts with the order expected from reactivity-selectivity. The tighter transition structure indicated by comparison of these α values is explained by a less favourable acylium ion in the case of the N-methylisonicotinyl transfer reaction.
Kinetics and mechanism of aminolysis of phenyl acetates and phenyl trimethylacetates in dimethyl suldoxide
Koh, Han Joong,Kim, Seung Il,Lee, Byung Choon,Lee, Ikchoon
, p. 1353 - 1358 (2007/10/03)
Kinetic studies have been carried out on the reactions of phenyl acetates and phenyl trimethylacetates in dimethyl sulfoxide.The rate ratios between the two acyl compounds, and the positive sign and large magnitude of the cross-interaction constants, ρXZ, between substituents X in the nucleophile and Z in the leaving group are considered to favour the rate-limiting expulsion of aryl oxide from the tetrahedral intermediate T+/-.The aprotic solvent used makes the proposed mechanism with a cyclic transition state more attractive especially in view of the greater charge dispersion and assistance to leaving group departure provided in such a structure.
