Pyrazoles. VIII. Rearrangement of N-nitropyrazoles. Formation of 3-nitropyrazoles

Habraken, Clarisse L.; Janssen, Johann

doi:10.1021/jo00820a004

Cited by 38 publications

(18 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Under similar conditions, compound 9 was formed rather than the aminated product by reacting 8 with THA. The structures of 5 and 7 are supported by IR, MS, and 1 H, 13 C, 15 N NMR spectroscopic data as well as elemental analysis. Structure conrmation of 7 by single-crystal X-ray diffraction analyses is given in Fig.…”

Section: Resultsmentioning

confidence: 79%

“…N-Methylated energetic compounds are particularly interesting for their relative lower melting points and sensitivities. Compound 11 was prepared in good yield using a literature procedure 18 and was reacted with hydrazine monohydrate in ethanol leading to a yellow precipitate, 14, characterized by 1 H, and 13 C NMR, MS and elemental analysis. The neutral species, 15, was isolated as the monohydrate (based on elemental analysis and IR (Scheme 2)) in high yield (88%) by reacting 14 with 10% HCl.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

4-Chloro-3,5-dinitropyrazole: a precursor for promising insensitive energetic compounds

et al. 2013

View full text Add to dashboard Cite

A series of 3,5-dinitropyrazole derivatives was prepared from 4-chloro-3,5-dinitropyrazole in good yields and characterized by IR, 1 H, and 13 C NMR (some cases 15 N NMR) spectroscopy, elemental analysis, and DSC. The structures of 7 and 13 were confirmed by single crystal X-ray diffraction. The impact sensitivity was determined using a standard BAM method, and detonation properties were obtained using experimental densities and calculated heats of formation.

show abstract

Section: Resultsmentioning

confidence: 79%

Section: Resultsmentioning

confidence: 99%

4-Chloro-3,5-dinitropyrazole: a precursor for promising insensitive energetic compounds

et al. 2013

View full text Add to dashboard Cite

show abstract

“…3(5)-Nitropyrazole (1) was prepared according to Habraken and Janssen. 15 It was purified by crystallization in water. The same sample from which a single crystal was collected for crystallography was used for the pK a determination.…”

Section: Introductionmentioning

confidence: 99%

Structure of 3-nitropyrazole in solution and in the solid state

Foces‐Foces

Llamas-Saíz

Menéndez

et al. 1997

J. Phys. Org. Chem.

View full text Add to dashboard Cite

The molecular and crystal structure of 3-nitropyrazole was determined by X-ray analysis. The triclinic unit cell contains 12 molecules which form four hydrogen-bonded (N-H···N) trimers. Each trimer comprises of pseudo-ring in a flattened envelope distorted towards a chair conformation. The crystal packing consists of layers formed by centrosymmetric related trimers joined through C-H···O interactions. Ab initio calculations were performed on 3(5)-nitro-and 4-nitropyrazole and their corresponding protonated forms up to the MP2/6-31G** level of theory. The origin of the difference in aqueous basicities between both nitropyrazoles is discussed.

show abstract

“…As a typical heterocyclic compound, 3-NP is an important intermediate in the synthesis of pyrazole-based compounds such as 3,4-dinitropyrazole (DNP) and other new explosives [36,38]. In 1970, Habraken and co-authors [39] firstly reported synthesis of 3-NP by dissolving N-nitropyrazole in anisole for 10 h at 145 • C. Later, Verbruggen et al [40] synthesized 3-NP from diazomethane and chloronitroethylene by one-step cyclization, while this reaction was high riskful due to the extremely vivacious raw materials. Nowadays, the main synthesis method of 3-NP was a two-step reaction, that is, nitration of pyrazole to obtain N-nitropyrazole and then rearrangement of N-nitropyrazole in organic solvent to acquire 3-NP ( Figure 1, Scheme A).…”

Section: Mononitropyrazoles and Their Derivativesmentioning

confidence: 99%

Recent Advances in Synthesis and Properties of Nitrated-Pyrazoles Based Energetic Compounds

et al. 2020

View full text Add to dashboard Cite

Nitrated-pyrazole-based energetic compounds have attracted wide publicity in the field of energetic materials (EMs) due to their high heat of formation, high density, tailored thermal stability, and detonation performance. Many nitrated-pyrazole-based energetic compounds have been developed to meet the increasing demands of high power, low sensitivity, and eco-friendly environment, and they have good applications in explosives, propellants, and pyrotechnics. Continuous and growing efforts have been committed to promote the rapid development of nitrated-pyrazole-based EMs in the last decade, especially through large amounts of Chinese research. Some of the ultimate aims of nitrated-pyrazole-based materials are to develop potential candidates of castable explosives, explore novel insensitive high energy materials, search for low cost synthesis strategies, high efficiency, and green environmental protection, and further widen the applications of EMs. This review article aims to present the recent processes in the synthesis and physical and explosive performances of the nitrated-pyrazole-based Ems, including monopyrazoles with nitro, bispyrazoles with nitro, nitropyrazolo[4,3-c]pyrazoles, and their derivatives, and to comb the development trend of these compounds. This review intends to prompt fresh concepts for designing prominent high-performance nitropyrazole-based EMs.

show abstract

Pyrazoles. VIII. Rearrangement of N-nitropyrazoles. Formation of 3-nitropyrazoles

Abstract: S CH diene), 14.65 µ; nmr (DMSO-dg) 4.98-5.73 (m, 3 H), 6.70-7.38 (m, 2 ), 8.02-8.41 (m, 4, aromatic); mass spectrum m/e 218 (molecular ion), 150 (as expected for loss of the fragment NHCH=CHCH=CH").

Cited by 38 publications

References 3 publications

4-Chloro-3,5-dinitropyrazole: a precursor for promising insensitive energetic compounds

4-Chloro-3,5-dinitropyrazole: a precursor for promising insensitive energetic compounds

Structure of 3-nitropyrazole in solution and in the solid state

Recent Advances in Synthesis and Properties of Nitrated-Pyrazoles Based Energetic Compounds

Contact Info

Product

Resources

About