- Synthesis and Antimicrobial Efficacy of Some Novel Heterocyclic Acetyl Istain Derivatives
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A series of novel heterocyclic compounds containing N-acetyl isatin moiety were synthesized. Herein, reaction of N-acetyl isatin with water in the presence of a catalytic amount of glacial acetic acid, via a ring opening route, yielded 2-(2-acetamidopheny
- Abuzeid, Mahmoud A.,Aly, Moustafa F.,Dardeer, Hemat M.,Elboray, Elghareeb E.
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p. 341 - 351
(2022/01/20)
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- The amide C-N bond of isatins as the directing group and the internal oxidant in Ru-catalyzed C-H activation and annulation reactions: Access to 8-amido isocoumarins
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The N-O, N-N and O-O bonds are the frequently used internally oxidative directing groups used in various redox-neutral coupling reactions. The sole use of the C-N bond as the oxidizing directing group was reported recently by Li X. and co-workers for the Rh(iii)-catalyzed C-H activation of phenacyl ammonium salts. Herein, we report the use of the amide C-N bond of isatins as the oxidizing directing group for the Ru(ii)-catalyzed redox-neutral C-H activation and annulation reactions with alkynes which afford 8-amido isocoumarins. The reaction also features excellent regioselectivity with alkyl aryl substituted alkynes.
- Kaishap, Partha Pratim,Sarma, Bipul,Gogoi, Sanjib
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supporting information
p. 9809 - 9812
(2016/08/04)
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- Mechanism of Photoinduced Reactions between 1-Acetylisatin and Aldehydes
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Hydrogen atom abstraction from aliphatic (2a, 2b) and aromatic (2c, 2d, 2e) aldehydes by the triplet nπ* state of 1-acetylisatin (1) yielded triplet (isatin ketyl-aldehyde acyl) radical pairs, which follow an out-of-cage pathway in subsequent reactions to give a series of radical coupling products 4-7. This out-of-cage mechanism is supported by examination of the primary products at various degrees of conversions during the course of the reaction, by the results of addition reactions of thermally generated isatin acyl radical with neutral 1, and by calculation of the charge density distribution in the acyl radicals and in ground state 1. Therefore, the oxygen-philic attack of the acyl radical, which had escaped out of cage from the triplet radical pair, at the C(3) carbonyl oxygen atom of a ground state 1 selectively afforded the thermodynamically more stable addition radical B. The recombination of two radicals B gave the 3-indolinone dimers 4 and 5 as diastereomers, while coupling of B with the isatin ketyl furnished the dihydroisoindigo derivative 6. Isatide 7 was also formed by ketyl radical recombination. The product ratio is dependent on the structure of the aldehyde. For 2d and 2e, each with an electron-donating substituent in the benzene ring, the corresponding acyl radicals are less electrophilic because of a diminished positive charge density at the carbonyl carbon atom, and the formation of the addition radical B is a slow process relative to the encounter and recombination of the isatin ketyl radicals. As a result, products 6d and 6e from cross-coupling of the isatin ketyl and radical B are formed in much lower yields than 6a, 6b, and 6c. The 3-acetyloxy-2-indolinone 3 turned out to be a secondary product derived from the decomposition of 6 during the workup procedures. Since all the primary products are formed by out-of-cage radical pair combination processes, no chain mechanism is involved. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
- Zhang, Yan,Wang, Lei,Zhu, Ye,Xu, Jian-Hua
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p. 527 - 534
(2007/10/03)
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- SEMICARBAZONES AND THIOSEMICARBAZONES OF THE HETEROCYCLIC SERIES. XLVII. ACYLATION OF ISATIN
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Contrary to previous data, the acylation of isatin by carboxylic acid anhydrides in the presence of perchloric acid leads to the formation not of the O-acyl derivatives but of the N-acyl derivatives, which have a noncoplanar structure.Their transformation into isatin hydrazone and oxime is due to hydrolysis of the N-acyl group.In alcohol solutions the N-acylisatins rapidly open the five-membered ring with the addition of an alcohol molecule.
- Tomchin, A. B.,Fradkina, S. P.,Krylova, I. M.,Khromenkova, Z. A.
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p. 2163 - 2172
(2007/10/02)
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