The Nitration of α- and β-Acylnaphthalenes

1995 ◽  
Vol 48 (12) ◽  
pp. 1969 ◽  
Author(s):  
SD Barker ◽  
K Wilson ◽  
RK Norris

The nitration of α- and β- acylnaphthalenes with copper(II) nitrate in acetic anhydride or nitric acid/acetic acid mixtures gives high yields of the corresponding mononitro compounds. The assignment of constitution to these products is made on the basis of extensive 1H n.m.r. chemicl shift and coupling constant data. In the case of α- acylnaphthalenes, with the notable exception of α- pivalonaphthone, nitration occurs in the α-positions of the unsubstituted ring to give mixtures of 5- and 8-nitro compounds. α- Pivalonaphthone gives appreciable amounts of the 4-nitro compound and also of the 8-nitro compound. This result indicates that the pivaloyl group does not shield the 8-position sterically to any significant extent and is effectively electronically neutral, unlike the other acyl substituents , in allowing attack at the α-position (position 4) of the acylated ring. This result is ascribable to the lack of coplanarity of the pivaloyl group with the naphthalene system. All of the β- acylnaphthalenes gave mixtures of 4-, 5- and 8-nitro derivatives in proportions that did not vary significantly with the nature of the acyl group.

2013 ◽  
Vol 9 ◽  
pp. 8-14 ◽  
Author(s):  
Yan Sun ◽  
Jing Sun ◽  
Chao-Guo Yan

A fast and convenient protocol for the synthesis of novel spiro[dihydropyridine-oxindole] derivatives in satisfactory yields was developed by the three-component reactions of arylamine, isatin and cyclopentane-1,3-dione in acetic acid at room temperature. On the other hand the condensation of isatin with two equivalents of cyclopentane-1,3-dione gave 3,3-bis(2-hydroxy-5-oxo-cyclopent-1-enyl)oxindole in high yields. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.


1966 ◽  
Vol 44 (17) ◽  
pp. 2009-2014 ◽  
Author(s):  
R. T. Coutts ◽  
J. B. Edwards

4-(2-Nitrobenzylidene)-2-pyrazolin-5-ones (I) were best prepared by heating o-nitrobenzaldehyde and 2-pyrazolin-5-ones in acetic anhydride containing fused sodium acetate (cf. Erlenmeyer azlactone synthesis). Pyrazolones of type I were reductively cyclized with cyclohexene and palladium–charcoal, and gave 3a,4,9,9a-tetrahydro-9-hydroxy-1H-pyrazolo-[3,4-b]quinolines (II) which, as expected, were amphoteric compounds. Of the three other methods of reduction used in this study, two (zinc and acetic acid; sodium borohydride and palladium–charcoal) were capable of producing pyrazoloquinolines, but were less reliable. The other method employed (hydrazine hydrate and palladium–charcoal) caused degradation of the pyrazolone molecule in the two cases examined, and in both, bis(2-aminobenzylidene) hydrazine (V) was the reduction product isolated.


1953 ◽  
Vol 31 (3) ◽  
pp. 214-215 ◽  
Author(s):  
R. A. Marcus ◽  
C. A. Winkler

An analytical method has been developed for the estimation of nitric acid in acetic acid – acetic anhydride media, with a precision of 0.3%. The procedure involves the addition of a solution of potassium acetate in acetic acid to the sample. The excess is back-titrated conductometrically with a standard solution of nitric acid in acetic acid.


1984 ◽  
Vol 49 (6) ◽  
pp. 1342-1353 ◽  
Author(s):  
Dragica Dumanović ◽  
Janka Ćirić ◽  
Djuro Kosanović ◽  
Dragoslav Jeremić

Based on systematic investigation of mononitroimidazoles, selective polarographic and spectrophotometric methods for determination of nitrazole compounds in reaction mixture are proposed. It was proved that the selectivity is based on the different properties of the nitro group due to the effects of the nitro group position in the ring, the type and position of the other substituents and on the fact whether the compound is N-substituted or not. The proposed methods can be successfully used for monitoring the synthetic procedures and decreasing the number of experiments for optimization. Based on the anticipated and proved behaviour of the nitro compounds of pyrazole, novel mononitropyrazole derivatives were synthetized in a new way and with high yields. Applying the polarographic method it was discovered that during N-substitution of tautomeric mononitroimidazole and mononitropyrazole substrates other byproducts were obtained besides the main products and undesired isomers. The products were identified and then a correct and more complete N-substitution scheme could be given. Following quantitatively these N-substitution processes conclusions which directly concern the mechanism of reactions were drawn.


1856 ◽  
Vol 146 ◽  
pp. 15-19

By submitting the nitro-compounds of the series of hydrocarbons, of which benzole is the lowest term, to Zinin’s well-known process, chemists have successively obtained the organic bases corresponding to these hydrocarbons. Aniline, toluidine, xylidine and cumidine have been prepared in this manner. Aniline was obtained by this process by Zinin* himself in 1845; toluidine by Muspratt and Hofmann†, in 1845; xylidine by Cahours‡, in 1850; and cumidine by Nicholson, in 1847§. Whilst the last-named chemist was engaged in the laboratory of the Royal College of Chemistry with the study of cumidine, the derivative of cumole, Dr. Noad, at the suggestion of Dr. Hofmann, pursued the same direction of research towards cymole, the only remaining hydrocarbon of this group, with a view of completing the series of the alkaloids||. In his experiments on the action of concentrated nitric acid on cymole, Dr. Noad found that this hydrocarbon differs somewhat from the other members of the series. Instead of furnishing the nitro-substitute, which is the link of connexion between the hydrocarbon and the alkaloid, cymole was found to undergo a partial oxidation, a portion of the carbon being eliminated in the form of carbonic acid with the simultaneous formation of several acids which belong to a group of bodies standing lower in the scale of organic compounds. The study of these very interesting acids, toluylic and nitrotoluylic, appears to have detached Dr. Noad’s attention from the formation of the substitution-product of cymole; and when he again returned to this inquiry he soon quitted it, in order to pursue still further a research in which he had already been successful¶. At the suggestion, and under the direction of Dr. Hofmann, the following investigation has been made, in the hope of filling up a gap still existing in the series of bases, and the desired alkaloid has been obtained; thus completing the inquiry which was commenced in the Royal College of Chemistry seven years ago.


1967 ◽  
Vol 21 ◽  
pp. 2296-2298 ◽  
Author(s):  
Salo Gronowitz ◽  
Anders Hallberg ◽  
J. Sandström ◽  
S. J. Cyvin ◽  
G. Hagen

2019 ◽  
Vol 71 (1) ◽  
Author(s):  
Kefa K. Onchoke ◽  
Jorge J. Ojeda

Abstract Three mono-nitrobenzanthrone isomers (1-, 2-, and 3-nitrobenzanthrone; 1-, 2-, and 3-NBA) were synthesized by reacting benzanthrone (BA) with nitric acid (HNO3) in acetic anhydride at ice-cold conditions. The major product, 2-nitrobenzanthrone (2-NBA), was confirmed using GC-MS via comparisons with a standard sample. On the basis of the elution profiles and fragmentation patterns two other isomers formed were assigned to 1-, and 3-nitrobenzanthrone (1-, and 3-NBA). The average percent yields of 1-, 2-, and 3-NBA were 0.3 ± 0.1%, 10.5 ± 2.6 %, and 6.4 ± 1.3 %, respectively.


1975 ◽  
Vol 53 (11) ◽  
pp. 1570-1578 ◽  
Author(s):  
Alfred Fischer ◽  
Colin Campbell Greig ◽  
Rolf Röderer

Nitration of 3,4-dimethylacetophenone in acetic anhydride gives a mixture of cis-and trans-2-acetyl-4,5-dimethyl-4-nitro-1,4-dihydrophenyl acetate as the main product, together with 3,4-dimethyl-2-, 3,4-dimethyl-5-, and 3,4-dimethyl-6-nitroacetophenone. Analogous products are obtained from 3,4-dimethylbenzophenone. Rearomatization of the adducts under mildly acidic conditions occurs via 1,4-elimination of nitrous acid to form 2-acetyl- and 2-benzoyl-4,5-dimethylphenyl acetate, respectively. In strongly acidic conditions elimination of acetic acid accompanied by 1,2- and 1,3-shifts of the nitro group occurs to form the 2- and 5-nitro derivatives of the parent ketones. The rearomatization to the nitro derivatives involves the intermediate formation of an ipso-cyclohexadienyl cation which may be trapped by anisole or mesitylene to form biphenyl derivatives.


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