The effect of the carbonyl group on the electrochemical reduction of azometine derivatives of α-diketones: reduction of isatin-3-oxime ethylether

1972 ◽  
Vol 17 (8) ◽  
pp. 1524-1528 ◽  
Author(s):  
R. Andruzzi ◽  
M.E. Cardinali ◽  
A. Trazza
Keyword(s):  
Electrochemical Reduction ◽  
Carbonyl Group ◽  
Derivatives Of

Polarographic reduction of α-(4-ethylbenzoyl)-α,β-dibromopropionic acid on mercury dropping electrode

1979 ◽  
Vol 44 (4) ◽  
pp. 1318-1323
Author(s):  
Miloslava Počtová
Keyword(s):  
Electrochemical Reduction ◽  
Carbonyl Group ◽  
Polarographic Reduction ◽  
Polarographic Wave ◽  
Intermediate Products ◽  
Active Intermediate

A mechanism of the electrochemical reduction of β-(4-ethylbenzoyl)-α,β-dibromopropionic acid is suggested based on the results of classical polarography and polarography with Kalousek's switch and on the identification of the polarographically active intermediate products. The substance converts to β-4-ethylbenzoylacrylic acid on the electrochemical elimination of the bromine atoms, and the latter acid is reduced further to β-4-ethylbenzoylpropionic acid. The most negative polarographic wave corresponds to the reduction of the carbonyl group in the benzoyl part of the last acid.

Electrochemical reduction of para-substituted 2-acyl-5-phenylfuranes in dimethylformamide

1981 ◽  
Vol 46 (2) ◽  
pp. 498-502 ◽  
Author(s):  
Jozef Černák ◽  
František Tomanovič ◽  
Andrej Staško ◽  
Anna Fedosyevna Oleinikova ◽  
Jaroslav Kováč
Keyword(s):  
Electrochemical Reduction ◽  
Unpaired Electron ◽  
Anion Radical ◽  
Electron Wave ◽  
Epr Method ◽  
Electron Center ◽  
Nitrogen Nucleus ◽  
Nitro Derivatives ◽  
Stable Anion ◽  
Derivatives Of

para Substituted chloro, bromo, and nitro derivatives of 2-acyl-5-phenylfurane are reduced polarographically in a one-electron wave to the corresponding anion radicals, which were studied by the EPR method. The reduction of nitro derivatives, studied by the Kalousek switch, is reversible and leads to a stable anion radical with an unpaired electron center on the nitrogen nucleus; the reduction of the halogen derivatives is only partly reversible and leads to unstable ketyl radicals. The bromo derivatives give polarographic maxima typical for concurrent reactions.

scholarly journals Fates of imine intermediates in radical cyclizations of N-sulfonylindoles and ene-sulfonamides

2015 ◽  
Vol 11 ◽  
pp. 1649-1655 ◽  
Author(s):  
Hanmo Zhang ◽  
E Ben Hay ◽  
Stephen J Geib ◽  
Dennis P Curran
Keyword(s):  
Carbonyl Group ◽  
Ring Opening ◽  
Radical Cyclizations ◽  
Type Reaction ◽  
Primary Products ◽  
Lactam Carbonyl Group ◽  
Lactam Carbonyl ◽  
Imine Reduction ◽  
Derivatives Of

Two new fates of imine intermediates formed on radical cyclizations of ene-sulfonamides have been identified, reduction and hydration/fragmentation. Tin hydride-mediated cyclizations of 2-halo-N-(3-methyl-N-sulfonylindole)anilines provide spiro[indoline-3,3'-indolones] or spiro-3,3'-biindolines (derived from imine reduction), depending on the indole C2 substituent. Cyclizations of 2-haloanilide derivatives of 3-carboxy-N-sulfonyl-2,3-dihydropyrroles also presumably form spiro-imines as primary products. However, the lactam carbonyl group facilitates the ring-opening of these cyclic imines by a new pathway of hydration and retro-Claisen-type reaction, providing rearranged 2-(2'-formamidoethyl)oxindoles.

Reaktionsverhalten von β-Oxo-carbonsäurederivaten der Anthracenreihe bei der Synthese von Pyrazolen / On the Reaction Behavior of ß-Oxo Carbonic Acid Derivatives of the Anthracene Series in Pyrazole Synthesis

1999 ◽  
Vol 54 (9) ◽  
pp. 1133-1137
Author(s):  
Astrid Knieß ◽  
Margit Gruner ◽  
Roland Mayer
Keyword(s):  
Carbonyl Group ◽  
Carbonic Acid ◽  
Ester Group ◽  
Reaction Behavior ◽  
Anthracene Derivatives ◽  
Sterical Hindrance ◽  
Derivatives Of

ß-Oxo-1 and 9-anthracenepropionate (6 and 7) reacts with DMF-acetale to enaminones 10 and 11. The reaction of 2-(dimethylamino)methylen-substituted ß-oxo-1 -anthracenepropionate (10) with hydrazines yields 5-(l-anthracenyl)-pyrazol-4-carboxylates (13). In contrast, the cyclocondensation of 3-(9-anthracenyl)-2-(dimethylamino)methylen-3-oxo-propionate (11) with hydrazine hydrochlorides gives 4-(9-anthracenoyl)-5-hydroxy-pyrazoles (14). This is caused by the sterical hindrance of the carbonyl group of the anthracene derivatives in position 9; thus, the cyclocondensation proceeds via reaction of the ester group of the enaminone 11.

Thio derivatives of β-diketones and their metal chelates. XXIII. Adducts of nickel(II) chelates of fluorinated Monothio-β-diketones with nitrogen heterocycles

1976 ◽  
Vol 29 (6) ◽  
pp. 1209 ◽  
Author(s):  
SE Livingstone ◽  
JH Mayfield ◽  
DS Moore
Keyword(s):  
Carbonyl Group ◽  
Infrared Spectra ◽  
Nitrogen Heterocycles ◽  
Metal Chelates ◽  
Derivatives Of

Paramagnetic adducts of the nickel(11) chelates of the fluorinated monothio-β-diketones RC(SH)=CHCOCF3 (R = β-naphthyl, p-ClC6H4, m-ClC6H4, m-BrC6H4, m-MeC6H4, 3,4-Cl2C6H3) have been obtained with pyridine, y-picoline, 2,2'-bipyridyl, and 1,l0-phenanthroline. They are of the type NiL2(base)2 (L = RCS=CHCOCF3; base = py, γpic, �bpy, �phen). With 2,2',2"-terpyridyl two types of adduct were isolated: (a) mononuclear NiL2(trpy) and (b) trinuclear Ni3L6(trpy)2. The infrared spectra of all the adducts display v(C-O) in the range 1552-1580 cm-l; this band is characteristic of a bidentate monothio-β-diketonato ligand. The spectra of the mononuclear terpyridyl adducts display in addition a v(C=O) band at c. 1650 cm-1, indicating that one carbonyl group is not coordinated.

Free radicals in the electrochemical reduction of derivatives of 3,5-dinitro-1,2-dihydropyridine

1997 ◽  
Vol 33 (2) ◽  
pp. 184-189 ◽  
Author(s):  
Ya. Stradyn' ◽  
R. Gavar ◽  
L. Baumane ◽  
B. Vigante ◽  
G. Dubur
Keyword(s):  
Free Radicals ◽  
Electrochemical Reduction ◽  
Derivatives Of

Synthesis of 5H-dibenzo[a,d]cycloheptene-5-carboxylic acid and related compounds. 1,5-Hydride transfer to inductively destabilized carbonium ions

1968 ◽  
Vol 46 (23) ◽  
pp. 3665-3670 ◽  
Author(s):  
D. E. Horning ◽  
J. M. Muchowski
Keyword(s):  
Carboxylic Acid ◽  
Carbonyl Group ◽  
Isotope Effect ◽  
Hydride Transfer ◽  
Large Magnitude ◽  
Carbonium Ion ◽  
Carbonium Ions ◽  
Acid Catalyzed ◽  
Derivatives Of ◽  
Related Compounds

The synthesis of 10,11-dihydro-5H-dibenzo[a,d]cycloheptene-5-carboxylic acid (2) and several derivatives of 5H-dibenzo[a,d]cycloheptene-5-carboxylic acid (1; a–c) from 5-hydroxy-10,11-dihydro-5H-dibenzo[a,d]cycloheptene-5-carboxylic acid and derivatives thereof (3; a–c) is described.The p-toluenesulfonic acid-catalyzed elimination of water (at 110.6° in toluene) from the deuterated hydroxy ester (3b; C-10, 11 d2) resulted in the incorporation of deuterium at C-5 of the olefinic ester 1b with a KH/KD of 2.76. The large magnitude of this isotope effect indicated that the reaction proceeded via a rate-determining transannular 1,5-hydride transfer from one of the benzylic positions of 3b to the carbonium ion generated alpha to the methoxy-carbonyl group.

Hydrogen bonding, configuration and conformation of substituted α-oxo oximes and hydrazones

1979 ◽  
Vol 44 (8) ◽  
pp. 2494-2506 ◽  
Author(s):  
Otto Exner ◽  
Jorga Smolíková ◽  
Václav Jehlička ◽  
Ahmad S. Shawali
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Carbonyl Group ◽  
Intramolecular Hydrogen Bond ◽  
Benzene Solution ◽  
Dipole Moments ◽  
H Nmr ◽  
Intramolecular Hydrogen ◽  
Derivatives Of ◽  
Configuration And Conformation

Substituted 2-bromo-1-phenylglyoxal 2-phenylhydrazones IIIa-f exist in tetrachloromethane or benzene solutions prevailingly in E-configuration and in conformation A with an intramolecular hydrogen bond. The latter was evidenced by the N-H valence frequency at 3 290 cm-1 and by 1H NMR shifts with reference to derivatives without a carbonyl group - α-chlorobenzaldehyde phenylhydrazones V. From dipole moments of IIIa-d, measured in benzene solution, the contribution of the hydrogen bond (μH) was evaluated to 17 . 10-30 C m. This quantity is twice larger than in any other reported compound but the direction of the vector is as usual: approximately from H to N. In structurally similar derivatives of hydroxylamine, substituted 2-phenylglyoxylhydroximoyl chlorides IVa-d, no intramolecular hydrogen bond was detected; the dipole moments found were interpreted in terms of the Z-configuration and the prevailing conformation G.

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