Layered structures formed by dinitrobenzoic acids

3,5-dinitrobenzoic acid, 1 and 3,5-dinitro-4-methylbenzoic acid, 2, form cocrystals with 4,4′-bipyridyl but only the latter forms a layered structure, which can incorporate anthracene molecules. Furthermore, 2 forms a pillared type structure with thionicotinamide.     

A novel supramolecular assembly of 3,5-dinitro-4-methylbenzoic acid and trans-1,2-bis(4-pyridyl)ethene

A novel organic assembly, formed between 3,5-dinitro-4-methylbenzoic acid and trans-1,2-bis(4-pyridyl)ethene under hydrothermal conditions in the presence of Pr(III) and a layered structure obtained by direct co-crystallization of the reactants at ambient conditions is reported. The structures of the complexes were established, unambiguously, by single crystal X-ray diffraction methods.     

Hydrogen bond mediated open-frame networks in coordination polymers: supramolecular assemblies of Pr(III) and 3,5-dinitro-4-methylbenzoic acid with aza-donor compounds

A coordination assembly of 3,5-dinitro-4-methylbenzoic acid and Pr(III), synthesized by hydrothermal methods forms a host structure, which is stable up to 300 [degree]C, through C-HO hydrogen bonds and accommodates different types of guest species varying from simple molecules like water to larger molecules like trans-1,2-bis(4-pyridyl)ethene.     

Abraham model correlations for solute transfer into benzyl alcohol from both water and the gas phase

ABSTRACT

Experimental solubilities have been determined for anthracene, benzil, 2-chloroanthraquinone, 9-fluorenone, 2-hydroxybenzoic acid, 2-methoxybenzoic acid, 2-methylbenzoic acid, 3-methylbenzoic acid, phenothiazine, pyrene, and thioxanthen-9-one dissolved in benzyl alcohol at 298.15 K. The measured solubility data, combined with previously published activity coefficient and solubility data, are used to determine Abraham model correlations for solute transfer to benzyl alcohol from both water and from the gas phase. The derived Abraham model correlations were found to back-calculate the experimental partition coefficients and solubility ratios to within 0.14 log units (or less).     

Solvent-dependent coordination polymers: cobalt complexes of 3,5-dinitrobenzoic acid and 3,5-dinitro-4-methylbenzoic acid with 4,4'-bipyrdine

The synthesis, structure elucidation, and analysis of the self-assembly of Co(II) complexes of 3,5-dinitrobenzoic acid and 3,5-dinitro-4-methylbenzoic acid with 4,4'-bipyridine have been reported. Formation of the complexes and the self-assembly in the three-dimensional structures have been found to be dependent on the solvents (such as acetone, dimethly sulfoxide, etc.) employed for the synthesis of the aggregates. 3,5-Dinitrobenzoic acid forms two coordination polymers, 1a and 1b, from methanol and a mixture of methanol and acetone solvents, respectively, with entirely different recognition patterns. Similarly, 3,5-dinitro-4-methylbenzoic acid also forms two coordination complexes, 2a and 2b, incorporating the solvent of the reaction medium into the crystal lattice. Complex 2a forms a solvated channel structure, whereas 2b gives a bilayered structure, with the layers being separated by solvent of crystallization (dimethyl sulfoxide) molecules. All the complexes have been characterized by single-crystal X-ray diffraction studies. Complexes 1b, 2a, and 2b crystallize in a monoclinic lattice, but 1a adopts a tetragonal lattice. The unit cell dimensions are, for 1a, a = 8.095(1) A, b = 8.095(1) A, c = 46.283 (6) A, alpha = 90 degrees, beta = 90 degrees, and gamma = 90 degrees (space group P4(3)2(1)2, Z = 4), for 1b, a = 22.774(2) A, b = 11.375 (1) A, c = 22.533(2) A, alpha = 90 degrees, beta = 104.15(1) degrees, and gamma = 90 degrees (space group P2(1)/c, Z = 4), for 2a, a = 17.657(6) A, b = 18.709(4) A, c = 21.044(6) A, alpha = 90 degrees, beta = 108.68(3) degrees, and gamma = 90 degrees (space group, C2/c, Z = 8), and, for 2b, a = 11.025(5) A, b = 15.139(4) A, c = 11.443(4) A, alpha = 90 degrees, beta = 97.48(3) degrees, and gamma = 90 degrees (space group P2/n, Z = 2). In all the complexes 1a, 1b, 2a, and 2b, the basic interaction between Co(II) and 4,4'-bipyridine remains the same with the formation of linear Co-N dative bonds, but the carboxylates display various modes of interaction with Co(II). The average Co-N and Co-O distances are 2.161 and 2.108 A, respectively.     

A One-Pot Synthesis of 3-Nitro-and 3,5-Dinitro-2-Picolines

3-Nitro- and 3,5-dinitro-2-picoline were each prepared in a one-pot synthesis in high yield by treatment of the respective 2-chloro- 3-nitro- and 2-chloro-3,5-dinitropyridines with diethyl sodiomalonate, followed by hydrolysis and decarboxylation with 50% sulfuric acid.     

Nitropyrazoles 16. The use of methoxymethyl group as a protecting group for the synthesis of 4-methyl-3-nitro-5-R-pyrazoles

4-Methyl-3,5-dinitropyrazole prepared by nitration of 1,4-dimethylpyrazole readily reacts with methoxymethyl chloride and methyl vinyl ketone in acetonitrile in the presence of a base giving 1-methoxymethyl-4-methyl-3,5-dinitropyrazole and 4-methyl-3,5-dinitro-1-(3-oxobutyl)pyrazole, respectively. The action of the thioglycolanilide anion on 4-methyl-3,5-dinitro-1-(3-oxobutyl)pyrazole results only in the removal of 1-protecting group and the formation of 2-[(3-oxobutyl)thio]acetanilide, while the action of anionic S-nucleophiles on 1-methoxymethyl-4-methyl-3,5-dinitropyrazole leads to the substitution products of the 5-NO₂ group in which the methoxymethyl group can be removed by acid hydrolysis.     

2-Aryl-3,5-dinitro-1,2-dihydropyridines

The reaction of -nitroacetaldehyde with paraformaldehyde or aromatic aldehydes and ammonium acetate in acetic acid yielded 2-aryl-3,5-dinitro-1,2-dihydropyridines. Aromatic aldehydes, in an ethanol and acetic acid mixture, gave isomeric 3,5-dinitro-1,4-dihydropyridines in addition to 1,2-dihydropyridines. Physicochemical properties and reactivities of the compounds have been studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 64–70, January, 1993.     

Nitration of 2,3′-bithienyl

The nitration of 2,3′-bithienyl ( 1 ) with fuming nitric acid in acetic anhydride at 0° gives a mixture of 3-nitro- ( 2 ), 2′ -nitro- ( 3 ) and 5-nitro-2,3′-bithienyl ( 4 ) with relative percentages of 38.7%, 34.8% and 26.5%. When the nitration of 1 was carried out with fuming nitric acid in acetic acid at 20°, the same compounds 2, 3 and 4 were obtained, but with different relative percentages: 20.4%, 36.5% and 43.1% respectively. The results of the mononitration of 1 are compared with those obtained in other electrophilic substitutions and with the theoretical predictions. The further nitrations of 2, 3 and 4 with nitric acid in acetic anhydride at room temperature lead to the formation of five dinitro-2,3′-bithienyl isomers. Compound 2 gives a mixture of 2′,3-dinitro- ( 5 ) and 3,5′-dinitro-2,3′-bithienyl ( 6 ); compound 3 gives a mixture of 5 , 2′,5-dinitro- ( 7 ) and 2′,4-dinitro-2,3′-bithienyl ( 8 ); compound 4 gives 7 and 5,5′-dinitro-2,3′-bithienyl ( 9 ). The possible reasons of the formation of the various dinitro-2,3′-bithienyl isomers are discussed.     

Dendro-shaped blocks with arylsulfanyl fragments based on p-toluic acid

Chloromethylation of p-toluic acid affords 3,5-bis(chloro- methyl)-4-methylbenzoic acid whose subsequent treatment with arenethiols brings about spacer dendrimeric blocks containing polyfluoroarylsulfanyl fragments in a total yield of 60-75%.     

3-Azabicyclo[3.3.1]nonane Derivatives: IV. Synthesis of Amino Acids with 3-Azabicyclo[3.3.1]nonane Fragment

A series of 1.5-dinitro-3-azabicyclo[3.3.1]non-6-enes was prepared by reduction of 1-R-2,4- and 1-R-3,5-dinitrobenzenes with potassium borohydride followed by Mannich reaction with formaldehyde and amino acids. The molecular structure of (6-bromo-1,5-dinitro-3-azabicyclo[3.3.1]non-6-en-3-yl)acetic acid was studied by X-ray diffraction analysis. The mechanism of decomposition under electron impact was determined for (7-methoxy-1,5-dinitro-3-azabicyclo[3.3.1]non-6-en-3-yl)acetic acid.     

Aminonitropyridines and their N-oxides

2,6-Diamino-3,5-dinitropyridine 1-oxide has been prepared by mixed acid nitration of 2,6-diaminopyridine, followed by oxidation using hydrogen peroxide in acetic acid. 3,5-Dinitro-2,4,6-triaminopyridine has been prepared by oxidative amination of 2-chloro-3,5-dinitropyridine or 2,6-diamino-3,5-dinitropyridine using potassium permanganate in liquid ammonia, or by “vicarious nucleophilic amination” of 2,6-diarnino-3,5-dinitropyridine using hydroxylamine in aqueous potassium hydroxide. 3,5-Dinitro-2,4,6-triaminopyridine 1-oxide has been prepared by oxidation of 3,5-dinitro-2,4,6-triaminopyridine using hydrogen peroxide in acetic acid, and by “vicarious nucleophilic amination” of 2,6-diamino-3,5-dinitropyridine 1-oxide. Nmr spectroscopy and single crystal X-ray diffraction studies have shown that these compounds have the planar structures and intra- and inter-molecular hydrogen bonding necessary to confer on the materials the high density, the thermal and chemical stability, and the explosive insensitivity required for new insensitive energetic materials.     

Dinitrofuran derivatives

The synthesis and properties of twelve 2-substituted 3,5-dinitrofurans are described. These derivatives include bromo-, iodo-, azido-, hydroxy-, amino-, 3,5-dinitro-2-furanyl-, 5-nitro-2-furanyl-, acetamido-, and carbamate compounds.     

Nitration of 1-methyl-2-pyridone

Nitration of 1-methyl-2-pyridone with 70% nitric acid or fuming nitric acid at 0–20°C proceeds in the 3 and 5 positions to give a mixture of mononitro isomers, the structures of which were proved by PMR spectroscopy. Mainly 3,5-dinitro-1-methyl-2-pyridone is formed by the action of fuming nitric acid or a nitrating mixture at 90°.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1671–1673, December, 1973.     

Ipso nitration. Nitrodeformylation reactions in nitrothiophenealdehydes

Nitration of 4-nitro-2-thiophenealdehyde afforded 2,4-dinitrothiophene and small quantities of 4,5-dinitro-2-thiophenealdehyde; 5-nitro-2-thiophenealdehyde gave instead 3,5-dinitro-2-thiophenealdehyde as the main product and some 2,5-dinitrothiophene. The two dinitrothiophenes form through a nitrodeformylation reaction which represents an interesting example of the nitration at an ipso position in a strongly deactivated substrate.     

Regioselectively [15NO2]-labeled N-methoxypicramide and DPPH prepared by using crown ether and solid sodium [15N]nitrite

The present paper reports the regioselective [¹⁵NO₂]-labeling of N-methoxy-2,4,6-trinitroaniline and 2,2-diphenyl-1-picrylhydrazine (reduced DPPH). Starting from N-methoxy-2,6-dinitroaniline, or N-methoxy-2,4-dinitroaniline, nitration in methylene chloride with solid sodium [¹⁵N]nitrite and 15-crown-5-ether afforded N-methoxy-2,6-dinitro-4-[¹⁵N]nitroaniline and N-methoxy-2,4-dinitro-6[¹⁵N]nitroaniline, respectively. The same compounds could be prepared in higher purity by nitrodecarboxylation (ipso-substitution) under the same conditions starting from N-methoxy-4-carboxy-2,6-dinitroaniline (4-methoxyamino-3,5-dinitrobenzoic acid) and N-methoxy-2-carboxy-4,6-dinitroaniline (2-methoxyamino-3,5-dinitrobenzoic acid). Similarly,ipso-substitution of 2,2-diphenyl-1-(4-carboxy-2,6-dinitrophenyl)-hydrazine afforded, under the same reaction conditions, 2,2-diphenyl-1-(2,6-dinitro-4-[¹⁵N]nitrophenyl)-hydrazine. By¹H-NMR and¹³C-NMR it was also observed that under these reaction conditions a¹⁴NO₂ group can be replaced by a¹⁵NO₂ group.     

Thiophene series. Note IX . The absence of secondary steric effects in nucleophilic substitutions of thiophene derivatives: Kinetics of the reactions of 2-bromo-3,5-dinitrothiophene and 2-bromo-3,5-dinitro-4-methylthiophene with piperidine

The kinetics of the reactions of piperidine with 2-bromo-3,5-dinitrothiophcne (IV) and 2-bromo-3,5-dinitro-4-methylthiophene (III) have been measured in methanol, ethanol and benzene. Molecular model predictions were confirmed when the kinetic results (k_IV/k_III ? 2) demonstrated, for the first time, the absence of secondary steric effects for nucleophilic substitutions in thiophene compounds.     

Experimental and predicted solubilities of 3,4-dichlorobenzoic acid in select organic solvents and in binary aqueous–ethanol mixtures

Experimental solubilities are reported for 3,4-dichlorobenzoic acid dissolved in methyl butyrate, and in 16 alcohol, 5 alkyl acetate, 5 alkoxyalcohol and 6 ether solvents. Solubilities were also measured in nine binary aqueous–ethanol solvent mixtures at 298.15?K. The measured solubility data were correlated with the Abraham solvation parameter model. Mathematical expressions based on the Abraham model predicted the observed molar solubilities to within 0.12 log units.