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A simple, rapid, and sensitive method is developed for the simultaneous determination of hydrazine, methylhydrazine, and 1,1-dimethylhydrazine in waters based on precolumn derivatization with benzaldehyde and the determination of the resulting products by reversed-phase HPLC with spectrophotometric detection at 300, 282, and 298 nm, respectively. The effect of imine and micellar catalysis is applied for the first time to obtain hydrazine derivatives on their simultaneous presence. The conditions of derivatization are chosen: the type, pH and concentration of the buffer system; the concentration of the reagent and the surfactant; and the temperature and duration of the reaction. It is found that the derivatization reaction proceeds completely at pH 9.4 in the presence of a catalytic system based on 0.6 M ammonium and 87 mM sodium dodecyl sulfate, and also 3.5 mM reagent at room temperature for 5 min. The quantitative yield of the derivatization products is confirmed by ion chromatography. The limits of detection (S/N = 3) without additional preconcentration are 0.3, 2.3, and 1.3 μg/L, and the linearity range is 1–500, 7–1000, and 5–1000 μg/L for hydrazine, methylhydrazine, and 1,1-dimethylhydrazine, respectively.

We studied different approaches to the synthesis of polyfluoroalkyl-containing 1-methyl-4-nitrosopyrazoles, which are based on the cyclization of 4,4,4-trifluoro-3,3-dihydroxy-2-hydroxyimino-1-R-butan-1-ones or 2-hydroxyimino-1,3-diketones with methylhydrazine and on a one-pot sequential treatment of 1,3-diketones with sodium nitrite and methylhydrazine. It was found that the regioselectivity of the formation of 1-methyl-4-nitrosopyrazoles is affected by the steric factors of 1,3-dicarbonyl reagents. The study of the mycostatic effect of 4-nitrosopyrazoles showed that the introduction of a bulky polyfluoroalkyl or tert-butyl substituent leads to a decrease in their activity.

We report an efficient catalytic protocol that chemoselectively reduces nitroarenes to arylamines, by using methylhydrazine as a reducing agent in combination with the easily synthesized and robust...

Reaction of methylhydrazine with 1,3- and 1,4-diiodotetrafluorobenzene produced cocrystals with the oxidation product sym-hexahydro-1,4-dimethyltetrazine. In contrast, reaction of 1,1-dimethylhydrazine with 1,2-, 1,3-, and 1,4-diiodotetrafluorobenzene, as well as 1,3,5-triiodotrifluorobenzene, yielded cocrystals with tetramethylammonium iodide (NMe4I), via C–I bond scission. For each of the NMe4I cocrystals, different polymoprhs or cocrystal stoichiometries were obtained via the C–I bond scission route, than were obtained by direct reaction of the halobenzene and NMe4I by standard solution techniques.

An experimentally simple, efficient, and inexpensive catalyst system was developed for the N-arylation of imidazole, indole, pyrrole, alkyl alcohol amines, and alkyl amines with aryl iodides and bromides. The reaction proceeds in water-ethanol media at 120 °C for 12 h with Cu2O as the catalyst, 1-(2-methylhydrazine-1-carbonyl)-isoquinoline 2-oxide (L2) as the ligand, NaOH as the base to generate a wide range of N-arylated products in moderate to excellent yields. Aqueous medium, ease of operation, and broad substrate scope give the process a benign environmental profile.

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re-evaluated monomethylhydrazine [60-34-4] considering all toxicological end points. The acute toxicity of monomethylhydrazine is caused by depletion of gamma-aminobutyric acid leading to the effects on the central nervous system. Chronic and subchronic exposure induces haemolytic effects and adverse effects on the liver. In carcinogenicity studies, inhaled monomethylhydrazine caused tumours of the lungs, liver, blood vessels and olfactory epithelium in female mice and tumours of the nose and adrenal glands in male hamsters. Orally applied, it induced tumours of the lungs and liver in mice and tumours of the colon and small intestine in hamsters. Monomethylhydrazine therefore remains classified in Carcinogen Category 2 and no maximum concentration at the workplace (MAK value) can be derived. Monomethylhydrazine is genotoxic in vitro and in vivo and demonstrates a mutagenic potential in vitro. The substance forms methyl DNA adducts in vivo. On the basis of these effects and its structural similarity to 1,1-dimethylhydrazine and 1,2-dimethylhydrazine, which are genotoxic in germ cells, monomethylhydrazine has been classified in Germ Cell Mutagenicity Category 3 B. Monomethylhydrazine is irritating to the skin of dogs, guinea pigs and rabbits and to the eyes of rabbits. Although no valid studies considering dermal absorption are available, the ���H��� designation (for substances which can be taken up via the skin in toxicologically relevant amounts) has been retained because of the low dermal LD50 values in animals. Although no studies considering its sensitizing potential are available, the ���Sh��� designation (for substances which cause sensitization of the skin) has been retained because of its structural similarity to the known contact allergen hydrazine.

With the deepening of human spaceflight activities and the gradual increase of spacecraft size, the demand for orbital propellant refueling has become more and more important. The technology of orbital propellant refueling is of great significance for prolonging the spacecraft life and reducing its cost. At present, most of the spacecraft around the world use the propulsion systems based on chemical propellants (such as liquid two-component propellants nitrogen tetroxide and methylhydrazine). Large spacecraft (such as manned space station) have the characteristics of high value and long service life. In order to improve the economic efficiency of spacecraft, orbital propellant refueling is globally used to prolong their service life.

We report the selective photoinduced reduction of nitroarenes to N-arylhydroxylamines. The present methodology facilitates this transformation in the absence of catalyst or additives and uses only light and methylhydrazine. This noncatalytic photoinduced transformation proceeds with a broad scope, excellent functional-group tolerance, and high yields. The potential of this protocol reflects on the selective and straightforward conversion of two general antibiotics, azomycin and chloramphenicol, to the bioactive hydroxylamine species.

Approaches to the chromatographic determination of 1,1-dimethylhydrazine and two main products of its degradation (hydrazine and methylhydrazine) on their simultaneous presence are proposed using derivatization by 5-nitro-2-furaldehyde and multi-wavelength spectrophotometric detection of the formed derivatives in the visible spectral region. A combination of preliminary derivatization with separation in the reversed-phase HPLC mode and also ion-chromatographic separation with post-column derivatization allowed us to reach the limits of detection for analytes lower than 1 μg/L and to determine 1,1-dimethylhydrazine at the level of the maximum permissible concentration without preconcentration. The developed approaches were tested on an acid extract of a sample of peat bog soil collected at the place of impact of the first stage of a carrier rocket. The identity of the results obtained by different methods and the high level of soil pollution by hydrazines are shown.

1,1-Dimethylhydrazine is widely used as a fuel by some classes of carrier rockets. Being an extremely toxic and reactive substance, it gives a number of hazardous transformation products and poses a serious threat to the ecological state of the launch sites and territories used for landing of spent rocket parts. On the basis of studies of the retention of analytes on the sulfobetaine zwitterionic stationary phase, the HILIC–ESI-MS/MS method for simultaneous and rapid determination of unsymmetrical dimethylhydrazine and six major products of its transformation (methylhydrazine, N-nitrosodimethylamine, N,N-dimethylformamide, 1-methyl-1,2,4-1H-triazole, 1,1,4,4-tetramethyl-2-tetrazene, 1,1-dimethylguanidine) was developed. The achieved detection limits for the analytes were 0.02–7 μg L−1 and, for most compounds, they are significantly lower compared to the existing IC–MS/MS method. Direct combination of HILIC–MS/MS with preliminary pressurized extraction with acetonitrile allowed analysis of peat bog soils contaminated with rocket fuel within 40 min, including all sample preparation steps. The developed method was successfully tested on a sample of real soil from the falling place of the spent carrier rocket stage.

Cu2O/2,6-bis(2-methylhydrazine-1-carbonyl)pyridine 1-oxide was found to be an efficiently catalytic system for the N-arylation of imidazole, indole, benzimidazole, pyrrole, benzylamine and ethanolamine with aryl iodides and bromides by using NaOH as base in the presence of 20 mol% (n-Bu)4NBr, and water as solvent at 130 °C in 24 h, and giving the N-arylated products in moderate to excellent yields.

In this article we report on the mechanistic studies of the Michael addition of amines and hydrazines to nitrostyrenes. Under the present conditions, the corresponding N-alkyl/aryl substituted benzyl imines and N-methyl/phenyl substituted benzyl hydrazones were observed via a retro-aza-Henry-type process. By combining organic synthesis and characterization experiments with computational chemistry calculations, we reveal that this reaction proceeds via a protic solvent-mediated mechanism. Experiments in deuterated methanol CD3OD reveal the synthesis and isolation of the corresponding deuterated intermediated Michael adduct, results that support the proposed slovent-mediated pathway. From the synthetic point of view, the reaction occurs under mild, noncatalytic conditions and can be used as a useful platform to yield the biologically important N-methyl pyrazoles in a one-pot manner, simple starting with the corresponding nitrostyrenes and the methylhydrazine.

Supercritical water gasification technology has ability to process unsymmetrical dimethylhydrazine (UDMH) wastewater derived from launching spacecraft, missile or satellite realizing both harmless treatment and resource utilization due to its unique property. Owning advantages such as compact structure, highly reduced reactor volume, improved heat transfer efficiency and fully mixed reactants, a spiral continuous reactor was proposed based on the characteristics of UDMH wastewater. Methylhydrazine (MMH) was used as model compound on account of UDMH’s commercial unavailability. The degradation of MMH in supercritical water is determined as an apparent first-order reaction using initial rate method. The effect of different parameters including temperature (450–550 °C), feeding flow rate (10–75 g/min), feeding concentration (5–30 %), and catalyst type on gasification were systematically investigated and subsequently the migration of carbon and nitrogen was also concerned. Results showed that addition of KOH could make the carbon gasification efficiency approach 100 % with the maximum hydrogen yield up to 21.6 mol/kg under the condition of 500 °C, 23 MPa, feeding flow rate of 30 g/min, feedstock concentration of 10 %. The proportion of organic carbon in total carbon tended to decrease with the increase of temperature. Most of nitrogen (up to 99.7 % at most) was gasified within our experimental range.

An improved and safe process for the production of 1-methyl-3,5-dinitro-1H-1,2,4-triazole, a promising melt-cast explosive to replace TNT, is described starting from dicyandiamide and methylhydrazine. The key step in our procedure is generation of target compound by catalytic oxidation of 3,5-diamino-1-methyl-1,2,4-triazole nitrate with hydrogen peroxide at 65 to 70°C. The main advantage of our procedure is the use of modified catalytic oxidation system and improved reagent addition method, which enabled proper control of the reaction exotherm in a 2-l reactor. After solvent extraction, 1-methyl-3,5-dinitro-1H-1,2,4-triazole was obtained in up to 92.5% purity (HPLC) with 43% overall yield. An improved modification of 1-methyl-3,5-dinitro-1H-1,2,4-triazole with lower melting point was prepared, using carboxymethylcellulose sodium salt as a surfactant.

// Yun Liu 1 , Lei Fan 1 , Huihui Zhao 2 , Wei Xu 1 and Jianyong Li 1 1 Department of Hematology, The First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, China 2 Department of Hematology, The Second Hospital of Nanjing, Nanjing, China Correspondence to: Lei Fan, email: // Keywords : T-LGL leukemia, HLH, metronomic regimen Received : June 03, 2016 Accepted : February 20, 2017 Published : February 27, 2017 Abstract A 71-year-old man was diagnosed with T-Large granular lymphocytic (LGL) leukemia, which usually represents a relatively indolent clinical course. While the clinical manifestation of this patient we report herein was aggressive with lasting fever, splenomegaly and hemophagocytic lymphohistiocytosis (HLH). T-cell immunophenotype was CD3+CD4-CD8-CD5-CD7-TCRαβ+. After comprehensive evaluation, an adjusted chemotherapy regimen CEOP (cyclophosphamide, vincristine, etoposide, prednisone) with etoposide, a potential effective regimen for HLH was administrated to the patient. Although he received intensive regimen, the patient showed drug resistance and disease progression with central nervous system (CNS) involvement during treatment and showed only transiently response to intrathecal methotrexate, cytarabine and dexamethasone. Therefore, considering the refractory elderly patient with fragile physical condition, metronomic regimen T-PEPC (oral administration of thalidomide, prednisone, cyclophosphamide, etoposide and methylhydrazine) was recommended, which refers to the frequent even daily administration of cytotoxic drugs at comparatively low doses with minimal or prolonged drug-free breaks. The patient responded well to this treatment and remained symptom-free for 8-month follow-up. To our knowledge, this is the first case of reporting this unique immunophenotype of dual CD4-/CD8- with aggressive clinical course and CNS involvement that successfully treated with metronomic regimen, suggesting that low dose metronomic regimen could be a better option for elderly patient with aggressive T-LGL leukemia.

5-Nitro-2-furaldehyde, a new derivatizing agent for the spectrophotometric determination of hydrazine, methylhydrazine, and 1,1-dimethylhydrazine is proposed. It is characterized by high solubility in water and by a substantial difference in the positions of absorption bands of the formed colored derivatives. The kinetics of the reaction of analyte derivatization is studied, and reaction conditions (pH 5, concentration of derivatizing agent 2 mM, 60° C, duration 40 min) are optimized. The limits of detection are 5, 3, and 1.5 μg/L for hydrazine, methylhydrazine, and 1,1-dimetlhydrazine, respectively. A possibility of the spectrophotometric determination of analytes in their simultaneous presence using the Firordt method is shown. The developed approach is successfully applied to the analysis of polluted peat bog soil selected at a place of impact of the first step of a carrier rocket.

A series of novel bis(1,2,3-triazoles) derivatives 7a – m were synthe­sized by the 1,3-dipolar cycloaddition (click-reaction) of 1-methyl-3,5-bis(2-(prop-2-yn-1-yloxy)phenyl)-4,5-dihydro-1 H -pyrazole ( 5 ) with various aralkyl azides 6a – m in the presence of sodium ascorbate and copper sulphate with good yields. The required precursor 5 was synthesized by reacting ( E )-1,3-bis(2-hydroxyphenyl)prop-2-en-1-one ( 3 ) with methylhydrazine hydrate via 2,2′-(1-methyl-4,5-dihydro-1 H -pyrazole-3,5-diyl)diphenol 4 , followed by reaction with propargyl bromide. The homogeneity of all the newly synthesized compounds was checked by TLC. The IR, NMR, mass spectral data and ele­mental analysis were in accord with the assigned structure. The title com­pounds were evaluated for their antibacterial activity against various bacterial strains, i.e ., Escherichia coli , Pseudomonas aeruginosa , Staphylococcus aureus and Bacillus subtilis ; compounds 7f – 7h and 7j were found to be mod­erately active against the bacteria, when compared with that of the standard drug. Furthermore, the same library of compounds was evaluated for their anti­oxidant activity using the nitric oxide radical scavenging activity. The results of the study showed that compounds 7e – 7h and 7k–7m showed good radical scavenging activity.

Cereals and legumes are very easily damaged by fungi, including toxigenic fungi species such as Aspergillus flavus which can produce aflatoxins. Various methods have been carried out to reduce aflatoxin contamination in foods, including the use of plant extracts based antimicrobial compounds. One of indigenous herbs in Papua that has potency as natural antimicrobial is Kebar grass ( Biophytum petersianum Klotszch). The aims of this study were to investigate the chemical composition and the effect of kebar grass stem ethanol extract on the growth of toxigenic A. flavus. Kebar grass stem ethanol extract at concentrations of 5, 10, 15, 20, 25, and 30 mg mL -1 was tested on the growth of A. flavus in two types media i.e. corn based-medium and peanut based-medium . The result showed that kebar grass stem ethanol extract at concentration of 15 mg ml -1 in corn based-medium and peanut based-medium caused 100% growth inhibition of A. flavus . The major compounds in kebar grass stem ethanol extract were: Pyrocatechol, Methylhydrazine hydrochloride, 2-Fluoropropane, Isobutyric acid, 2,6-Dimethoxyphenol. The results obtained from this study suggested that the ethanol extract of the kebar grass stem can be used as a natural antifungal agent to inhibit the growth of aflatoxigenic A. flavus .

2-Aroylbenzoic acid was allowed to react with hydrazine hydrate, hydroxyl amine and methylhydrazine to afford the corresponding 5,6,7,8-tetrachlorophthalazin-1-one. The antimicrobial effect of the phthalazin-1-one in the water of the swimming pool and river can be discussed. DFT based on quantum chemical computational of the new compounds were synthesized with the objective of studying their antimicrobial activity. The newly synthesized compounds were characterized on the basis of their spectral (1H-NMR, Mass spectrum, IR and Elementary analysis

An efficient synthesis of hydrazones of 4-(3-oxobutyl)semicarbazides and 4-(3-oxobutyl)semicarbazones using novel semicarbazone-based amidoalkylation reagents, 1-arylidene-4-[(aryl)(tosyl)methyl]semicarbazides, has been developed. The synthesis involved reaction of the latter with the Na-enolate of acetylacetone, followed by a base-promoted retro-Claisen reaction and treatment of the obtained 4-(3-oxobutyl)semicarbazones with hydrazine or methylhydrazine. The prepared hydrazones were converted stereoselectively into 14-membered cyclic bis-semicarbazones under acidic conditions. Especially high selectivity ( trans / cis ⩾ 97:3) was observed upon the macrocyclization of 4-(3-oxobutyl)semicarbazone hydrazones. A plausible reaction pathway and the stereochemistry of this cyclization were discussed.

A variety of 5-aryl-2-methyltetrazoles and 5-aryl-2-benzyltetrazoles were directly prepared in good to moderate yields by the reaction of aromatic aldehydes with methylhydrazine and benzylhydrazine, followed by treatment with di-tert-butyl azodicarboxylate and [bis(trifluoroacetoxy)iodo]benzene in a mixture of dichloromethane and 2,2,2-trifluoroethanol at room temperature. The present method is a novel one-pot preparation of 5-aryl-2-methyltetrazoles and 5-aryl-2-benzyltetrazoles through a [2N + 2N] combination under transition metal-free and mild conditions.

Device and process of oxidization, degassing, acidity adjustment of 1BP (The Pu production feed from U/Pu separation section) from APOR process (Advanced Purex Process based on Organic Reductants) were improved through rational design and experiments. The device was simplified and the process parameters, such as feed position and flow ratio, were determined by experiments. Based on this new device and process, the reductants N , N -dimethylhydroxylamine (DMHAN) and methylhydrazine (MMH) in 1BP solution could be oxidized with much less N 2 O 4 consumption.

An ingress of highly toxic rocket fuel 1,1-dimethylhydrazine (UDMH) and its transformation products into environment represents a serious negative impact on the ecosystem, as well as human health. The present research demonstrates the first data on the spatial distribution and quantification of UDMH and its main transformation products (methylhydrazine, hydrazine, 1,1,4,4-tetramethyltetrazene, formaldehyde, acetaldehyde and furaldehyde N,N-dimethylhydrazones, 1-formyl-2,2-dimethylhydrazine, N,N-dimethylformamide, N-nitrosodimethylamine, and 1-methyl-1H-1,2,4-triazole) in the peat bog soil of the fall site in subarctic region. One hundred samples of peat bog soil and one sample of surface water were analyzed by the developed earlier methodology. The considerable amounts of UDMH and most of its transformation products were found at distances of not >10 m from the center of the fall site. The maximum concentration of UDMH was found near the center, where maximal permissible concentration (MPC) was exceeded 2400-fold. The greatest pollution was observed in the surface soil layer, while methylhydrazine, 1-methyl-1H-1,2,4-triazole, 1-formyl-2,2-dimethylhydrazine, formaldehyde and acetaldehyde N,N-dimethylhydrazones, and N,N-dimethylformamide were the major UDMH transformation products. With increasing distance from the center, the composition of the transformation products changes in favor of the last three compounds. Formaldehyde N,N-dimethylhydrazone and N,N-dimethylformamide are present in all soil samples and can be considered as reliable markers of contamination with rocket fuel. The surface water of the peat bog contained four UDMH transformation products in considerable concentrations, including extremely toxic N-nitrosodimethylamine. The processes of migration and transformation of UDMH in peat bog soil differ considerably from those in sandy soils. This is due to cold climate of subarctic zone, the reducing environment of peat bog, and strong binding of hydrazines to organic matter of peat, which prevents migration of pollutants and contributes to the long-term maintenance of high levels of soil pollution.

The data set covers the results of a study of 96 samples of peat bog soil from the fall place of the first stage of the Cyclone-3 launch vehicle contained unburned toxic rocket fuel 1,1-dimethylhydrazine (UDMH) in the European North of Russia. Soil samples were taken during a helicopter expedition to the “Koida” fall region of Plesetsk Cosmodrome operation zone in October 2015 at different distances from the center of the fall site and from different soil horizons. Samples were analyzed by liquid chromatography with amperometric detection and gas chromatography - tandem mass spectrometry. The contents of UDMH and the ten most important products of its transformations (methylhydrazine, hydrazine, 1,1,4,4-tetramethyltetrazene, formaldehyde, acetaldehyde and furaldehyde N,N-dimethylhydrazones, 1-formyl-2,2-dimethylhydrazine, N,N-dimethylformamide, N-nitrosodimethylamine, and 1-methyl-1H-1,2,4-triazole) were determined. The obtained data reflect the spatial distribution, migration and transformation of UDMH in the fall places of rocket stages under conditions of subarctic which is discussed in related research article “Migration and transformation of 1,1-dimethylhydrazine in peat bog soil of rocket stage fall site in Russian North” [1] . They can be further used for understanding the UDMH transformation pathways in soils rich in organic matter and assessment of environmental impact of space rocket activities in high latitudes.

Methylhydrazine-induced α-hydroxylation of β-dicarbonyl compounds was achieved using O2 as the oxygen source. This reaction provides an efficient approach to enantioenriched ɑ-hydroxy β-dicarbonyl compounds, which are valuable substances and widely used in the chemical and pharmaceutical industry. A wide variety of β-keto esters could undergo this oxidation to give the corresponding products in excellent yields (up to 95%) and with good enantioselectivities (up to 85% ee). The mild reaction conditions and the use of molecular oxygen as oxidant make this protocol very environmentally friendly and practical.

A promising alternative to ion-chromatographic methods currently used for the direct determination of hydrazines is provided by hydrophilic interaction liquid chromatography (HILIC). In this work, we propose a method for the simultaneous determination of hydrazine, methylhydrazine and 1,1-dimethylhydrazine in natural waters and soils based on a combination of chromatographic separation on a zwitterionic sulfobetaine stationary phase (Nucleodur HILIC) in the HILIC mode with amperometric detection. Effects of different factors on the retention of analytes were studied and the optimum conditions of analysis were found. We recommend a mixture of acetonitrile with an aqueous phosphate buffer solution of pH 2.5 (78:22 v/v) with an ionic strength of 20 mM as a mobile phase. Detection in the direct current mode was performed at a working electrode potential of 1.1 V. The advantages of the method are the high efficiency of separation, rapidity, high sensitivity and a wide dynamic range of analyte concentrations, covering four orders of magnitude. The attained LOD values for analytes lie in the range 0.07–0.13 μg L–1, which is two orders of magnitude lower than those in currently used methods of ion chromatography with electrochemical and mass spectrometric detection. The method was validated on samples of natural waters of different origin using the added–found technique. It was found that the error of analysis did not exceed 10% for river and ground waters and increased to 20–30% for peat bog surface waters. The possibility of application of the developed method to the analysis of soils was shown on samples of peat bog soils selected at places of impact of the first steps of carrier rockets and polluted by rocket fuel based on 1,1-dimethylhydrazine.

This paper firstly describes an efficient and regioselective method for the synthesis of a new series of 2,2,2-trifluoro-1-[4-methoxy-spiro(2 H -chromen-2,1′-cycloalkane)-3-yl]ethanones from spiro[chroman-2,1′-cycloalkan]-4-ones (Kabbe's adduct). Yields of 38–61% were obtained when trifluoroacetylation reactions of mixtures of enolethers and/or acetals derived from four spiro ketones (Kabbe's adduct) were performed at a temperature of 45 °C, employing anhydrous chloroform as the solvent. Subsequently, when the respective trifluoroacetylated Kabbe adducts reacted with phenylhydrazine and methylhydrazine at a 1:1 molar ratio in refluxing ethanol for 24 h, a new series of seven examples of a new spiro-condensed heterocyclic system, namely 1(2)-methyl(phenyl)-3-(trifluoromethyl)-1,4(2,4)-dihydro-spiro(chromen[4,3- c ]pyrazole-4, n ′-cycloalkanes) – where cycloalkanes are cyclopentane, cyclohexane, and cycloheptane for n = 1; and tetrahydro-2 H -pyran for n = 2 – were isolated at yields of between 35% and 51%. Finally, the structures of new spiro heterocycles were determined with the aid and simultaneous application of 1 H, 13 C and 19 F one-dimensional and gHMBC NMR experiments, X-ray monocrystal diffraction, and mass spectrometry techniques.

Reactions between CH3NHNH2 and OOH radical were studied using computational methods. The activation energies (Ea) and Gibbs free energies of activation (ΔG#) were calculated at the MP2 and B3LYP levels of theory. The calculated activation energies of the hydrogen abstraction reactions were less than 100 kJ/mol and those for the substitution reactions were about 150–250 kJ/mol. The calculated activation energies for the intra-molecular hydrogen transfer reactions in CH3NHNH, CH2NNH2 and CH3NN molecules were 210–250 kJ/mol. Catalytic effect of the water molecule on the intra-molecular hydrogen transfer reactions was studied. It was found that the water molecule decreases the activation energies by about 70–100 kJ/mol. Rate constants of the reactions were calculated using transition state theory in the temperature range of 298–2000 K. Consecutive hydrogen abstraction reactions from CH3NHNH2 led to the formation of CH2NN, which was a very stable molecule.

The 2,2-dimethyl-5-[(2-metylhydrazinyl)methylidene-1,3-dioxan-4,6-dione has been prepared and its crystal structure of 2,2-dimethyl-5-[(2-metylhydrazinyl)methylidene-1,3-dioxan-4,6-dione (C8H12O4, Mr = 200.19) has been determinated by single-crystal X-ray diffraction analysis. The compound crystallizes in the monoclinic system with space group C2/c and unit cell parameters: a = 27.9436(6), b = 10.1683(3), c = 14.1604(3) A, β = 100.334(2)° and Z = 16. The final reliability index is 0.0412 for the 2866 observed reflections. The two molecules of 1 are localized in independent part of unit cell. The title compounds are linked through N–H⋯O, C–H⋯O and C–H⋯N hydrogen bonds into 1-D rail-like supramolecular chains. The 2,2-dimethyl-5-[(2-metylhydrazinyl)methylidene-1,3-dioxan-4,6-dione has been prepared and its crystal structure of 2,2-dimethyl-5-[(2-metylhydrazinyl)methylidene-1,3-dioxan-4,6- has been determinated by single-crystal X-ray diffraction analysis. .