Nitro group valence vibrations of polysubstituted nitrobenzenes

1971 ◽  
Vol 14 (5) ◽  
pp. 624-627
Author(s):  
A. E. Lutskii ◽  
G. G. Sheina ◽  
V. N. Konel'skaya ◽  
A. V. Belous
Keyword(s):  
Nitro Group ◽  
Group Valence

Effects of Ultrasounds on Neat nitrobenzene

2019 ◽  
Vol 70 (8) ◽  
pp. 3085-3088
Author(s):  
Carmen Eugenia Stavarache ◽  
Yasuaki Maeda ◽  
Mircea Vinatoru
Keyword(s):  
Nitro Group ◽  
Radical Cation ◽  
Reaction Mechanisms ◽  
Diphenyl Ether ◽  
Argon Atmosphere ◽  
Phenyl Radical ◽  
Dissolved Gas ◽  
Decomposition Products ◽  
Oxygenated Compounds ◽  
Phenyl Cation

Neat nitrobenzene was continuously irradiated at two ultrasonic frequencies: 40 and 200 kHz, under air and argon atmosphere, respectively. Samples taken at intervals of 1, 5, 10 and 24 h were analyzed by GC-MS and decomposition products were identified. Possible reaction mechanisms are discussed. Presence of air as dissolved gas leads to oxygenated compounds such as 1,4-benzoquinone, 2,4-dinitrophenol, m-dinitrobenzene while argon inhibits the decomposition of nitrobenzene, especially at sonication times under 5 h. Based on the nature of the compounds identified we advanced a mechanism, involving a divergent splitting of unstable radical cation of NB in air and argon respectively. Thus, under air, the phenyl cation formation is preferred leading to 1,4-benzoquinone nitro-biphenyls and dinitrobenzene, while under argon, the phenyl radical formation seems to be favored, leading to phenol and diphenyl ether. The oxygenated compounds detected under argon clearly are a consequence of the nitro group splitting.

Regioselectivity of nucleophilic aromatic photosubstitution in the biphenyl series. Photohydrolysis of some dimethoxynitrobiphenyls

1987 ◽  
Vol 52 (10) ◽  
pp. 2482-2491 ◽  
Author(s):  
Ján Urban ◽  
Petr Kuzmič ◽  
David Šaman ◽  
Milan Souček
Keyword(s):  
Nitro Group ◽  
Steric Hindrance ◽  
The Other ◽  
Quantum Yields ◽  
Hydroxide Anion ◽  
Tert Butanol ◽  
Nitro Derivatives

Anaerobic photolysis of dimethoxynitrobiphenyls IIIa-VIa in aqueous alkaline tert-butanol gave products of nucleophilic photosubstitution of methoxyl by hydroxide anion, while the dimethoxybiphenyls Ia and IIa were found unreactive. Regioselectivity of the reaction was examined in view of a possible “extended meta activation” by the nitro group. The most reactive substrate IIIa gives both C-3 and C-4 substitution products with an unsubstantial preference for the latter, which opposes the “extended meta selectivity” rule. All of the other compounds obey the rule, and 3,4-dimethoxy-3'-nitrobiphenyl (IVa) even displayed absolute selectivity by yielding C-3 substituted compound as the only product. 2,5-Dimethoxy substituted compounds underwent photosubstitution which much lower quantum yields than their 3,4-substituted counterparts, most probably due to some steric hindrance of conjugation. Similarly, 3-nitro-substituted biphenyls exhibited much lower overall reactivity than 4-nitro derivatives.

Photoreaction of N-butyl 3,4-dimethoxy-6-nitrobenzamide with butylamine. A model study for lysine-directed photoaffinity labelling

1987 ◽  
Vol 52 (7) ◽  
pp. 1780-1785 ◽  
Author(s):  
Petr Kuzmič ◽  
Libuše Pavlíčková ◽  
Milan Souček
Keyword(s):  
Nitro Group ◽  
Aromatic Ring ◽  
Ultraviolet Irradiation ◽  
Title Compound ◽  
Reductive Coupling ◽  
Photoaffinity Labelling ◽  
Photolysis Rate ◽  
Model Study ◽  
A Minor

Ultraviolet irradiation of the title compound I in the presence of butylamine gave predominantly products of nucleophilic photosubstitution by the amine, i.e., nitroanilines IIa and IIb. Besides, small amounts of products of hydrolysis (phenol III) and reductive coupling (azoxybenzene IV) were also formed. Comparison of the overall photolysis rate of I with that of 3,4-dimethoxy-1-nitrobenzene (V) indicates a minor loss of reactivity, most probably due to some deviation from coplanarity of the activating nitro group and the aromatic ring.

The X-Ray Molecular Structure of 1-(2′,4′-Dinitrophenyl)-1,2,3-triazole and the Problem of the Orthogonal Interaction Between a 'Pyridine-Like' Nitrogen and a Nitro Group

2005 ◽  
Vol 58 (11) ◽  
pp. 817 ◽  
Author(s):  
Glenn P. A. Yap ◽  
Fernando A. Jové ◽  
Rosa M. Claramunt ◽  
Dionisia Sanz ◽  
Ibon Alkorta ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Nitro Group ◽  
Title Compound ◽  
Theoretical Calculations ◽  
X Ray

The structure of the title compound serves for a discussion about the topic of orthogonal interactions. This interaction, although weak, is important due to its peculiar geometry. Other examples from the Cambridge Crystallographic Database, together with theoretical calculations are reported.

The preparation of 2-Fluoro-5-nitrobenzonitrile and the proton magnetic resonance spectra of some compounds containing the N-(2-Cyano-4-nitrophenyl) group

1967 ◽  
Vol 20 (8) ◽  
pp. 1663 ◽  
Author(s):  
JFK Wilshire
Keyword(s):  
Amino Acids ◽  
Magnetic Resonance ◽  
Nitro Group ◽  
Proton Magnetic Resonance ◽  
Cyano Group ◽  
Aromatic Nucleus ◽  
Heteroaromatic Compounds ◽  
Magnetic Resonance Spectra

2-Fluoro-5-nitrobenzonitrile, an analogue of 1-fluoro-2,4- dinitrobenzene, in which the 2-nitro group has been replaced by a cyano group, has been prepared and made to react with several amines, amino acids, and NH-heteroaromatic compounds. The proton magnetic resonance spectra of some of the resultant N-(2-cyano-4-nitrophenyl) derivatives were compared with the spectra of the corresponding N-(2,4- dinitrophenyl) derivatives and furnish further evidence that the ortho nitro group of the latter derivatives is rotated out of the plane of the aromatic nucleus.

Preparation of Functionalized Diorganomagnesium Reagents in Toluene via Bromine or Iodine/Magnesium-Exchange Reactions

Synthesis ◽  
2021 ◽  
Author(s):  
Alexandre Desaintjean ◽  
Fanny Danton ◽  
Paul Knochel
Keyword(s):  
Exchange Reaction ◽  
Nitro Group ◽  
General Formula ◽  
Functional Groups ◽  
Exchange Reactions ◽  
Acyl Chlorides ◽  
Aryl Iodides ◽  
Highly Sensitive ◽  
Wide Range ◽  
Magnesium Exchange

A wide range of polyfunctionalized di(hetero)aryl- and dialkenyl-magnesium reagents were prepared in toluene within 10 to 120 min between −78 °C and 25 °C via an I/Mg- or Br/Mg-exchange reaction using reagents of the general formula R2Mg (R = sBu, Mes). Highly sensitive functional groups, such as a triazene or a nitro group, were tolerated in these exchange reactions, enabling the synthesis of various functionalized (hetero)arenes and alkenes derivatives after quenching with several electrophiles including allyl bromides, acyl chlorides, aldehydes, ketones, and aryl iodides.

Colorimetric Determination of Aklomide (2-Chloro-4-Nitrobenzamide) in Poultry Feed

1969 ◽  
Vol 52 (3) ◽  
pp. 438-441
Author(s):  
Glenn M George ◽  
A C Daftsios ◽  
Joseph L Morrison
Keyword(s):  
Nitro Group ◽  
Poultry Feed ◽  
Colorimetric Determination ◽  
Average Recovery ◽  
Low Level ◽  
Color Development ◽  
Titanium Trichloride ◽  
High Level

Abstract The coccidiostat aklomide is extracted from feed with methanol and assayed colorimetrically by reduction of the nitro group to anamine with titanium trichloride and subsequent color development with t he Bratton-Marshall reaction. Thirteen laboratories studied the method collaboratively on two levels of medicated feed. Overall average recovery was 106.5% of the oretical for the low level and 104.5% of the oretical for the high level. The method is recommended for adoption as official first action

Nitrone Formation by Reaction of an Enolate with a Nitro Group

2021 ◽  
Vol 23 (7) ◽  
pp. 2704-2709
Author(s):  
Hiroaki Shimizu ◽  
Kohei Yoshinaga ◽  
Satoshi Yokoshima
Keyword(s):  
Nitro Group

THE IONIZATION CONSTANTS OF p-NITROPHENYLACETIC AND PHENYLMALONIC ACIDS

1933 ◽  
Vol 8 (5) ◽  
pp. 447-449 ◽  
Author(s):  
Steward Basterfield ◽  
James W. Tomecko
Keyword(s):  
Benzoic Acid ◽  
Nitro Group ◽  
Malonic Acid ◽  
Phenylacetic Acid ◽  
Ionization Constants ◽  
Side Chain ◽  
Cooh Group ◽  
Conductivity Data ◽  
Nitrobenzoic Acid ◽  
Phenylmalonic Acid

The ionization constants of p-nitrophenylacetic and phenylmalonic acids have been determined from conductivity data. The value of K for p-nitrophenylacetic acid at 25 °C. is 1.04 × 10−4, about twice that of phenylacetic acid. The nitro group in the nucleus has not as powerful an effect on the ionization when the COOH group is in the side chain as it has when both nitro group and COOH are in the nucleus. K for p-nitrobenzoic acid is six times as great as K for benzoic acid. K for phenylmalonic acid is 2. 77 × 10−3 as compared with 1.6 × 10−3 for malonic acid.

Sign in / Sign up

Export Citation Format

Share Document