Showing papers on "Hydrazine published in 1975"

The reduction of mono-coordinated molecular nitrogen to ammonia in a protic environment

Abstract: WE have reduced ligating molecular nitrogen (dinitrogen) to ammonia in yields of up to 90% at a single metal site This reaction is important for its possible application to our understanding of the chemical mechanism of the reduction of dinitrogen to ammonia by nitrogenase, where the reduction may occur at a single molybdenum ion site1 Our reaction occurs when compounds of the type [M(N2)2(PR3)4](I; M =Mo or W; R = alkyl or aryl) are treated at room temperature with sulphuric acid in methanol solution: This reaction was performed in a vacuum so that the evolved gases could be analysed and measured On mixing the reagents, one molecule of nitrogen gas was rapidly evolved with a trace of dihydrogen The remaining dinitrogen was spontaneously reduced to ammonia together with some hydrazine, presumably also with concomitant oxidation of the metal M

Plutonium partitioning in the Purex process with hydrazine-stabilized hydroxylamine nitrate

Abstract: The use of hydrazine-stabilized hydroxylamine nitrate (HAN) to partition plutonium from uranium in the Pur ex process was successfully demonstrated in a laboratory multistage contactor. Reduction rate constants for the HAN-Pu(IV) reaction were obtained and used in a generally satisfactory computer simulation of the partition behavior.

Catalytic reduction of aromatic nitro compounds with hydrazine in the presence of iron(iii) chloride and active carbon

Abstract: A catalytic reduction of aromatic nitro compounds to aromatic amino compounds with hydrazine in the presence of Fe(III) chloride and active carbon was studied. The corresponding amino compounds were obtained with excellent purities and in good yields. The method was also applied to the partial reduction of dinitro compounds.

Method for preparing aqueous, radioactive waste solutions from nuclear plants for solidification

Abstract: A method is provided for preparing aqueous, radioactive waste solutions, from reprocessing plants for spent nuclear fuel and/or breeder materials and other nuclear plants, for noncontaminating solidification and/or removal of such solutions. The total quantity of the various inorganic and organic substances in the waste solution is reduced by the destruction of nitric acid, nitrates and nitrites and the formation of a waste gas mixture which is practically free of higher nitrous oxides. To bring this about, the radioactive waste solutions are subjected to an electrolysis current at such current densities at the anode and at the cathode that in one process step the substances of the group hydrazine, hydroxylamine, oxalic acid, oxalates, tartaric acid and tartrates are oxidized at the anode and the substances of the group nitric acid, nitrates and nitrites are reduced at the cathode.

Cellulose solutions and products prepared therefrom

Abstract: Solutions of cellulose in hydrazine are formed by dissolving cellulose therein. The cellulose solutions formed may be utilized for the preparation of fibers, films, foams or other cellulose fabricated articles. Alternatively, the dissolution of cellulose in hydrazine may be employed as a means for the direct extraction of cellulose from lignocellulosic materials without the necessity of pulping operations.

Method for the preparation of rubbers with low molecular weights through degradation of macromolecular polyenes, and the products thus obtained

Abstract: An unsaturated hydrocarbon elastomer with a high molecular weight is reacted upon an oxidizer and a reducer forming a redox couple, in an organic solvent medium in the absence of air or in an aqueous medium, the oxidizer being selected from the group consisting of hydrogen peroxide and organic peroxides, and the reducer being selected from the group consisting of sulphinic acids and their derivatives and of hydrazine and its derivatives. The pasty to liquid materials obtained give, after having been vulcanized and possibly reinforced, elastomeric products.

Notiz zur Struktur des Umsetzungsproduktes von 4-Isothiocyanato-4-methyl-2-pentanon mit Hydrazin —Über das 2,4,5,6-Tetrahydro-5,5,7-trimethyl-3H-1,2,4-triazepin-3-thion

Abstract: On reaction of 4-isothiocyanato-4-methyl-2-pentanone (1) with hydrazine 2,4,5,6-tetrahydro-5,5,7-trimethyl-3H-1,2,4-triazepine-3-thione (4 a) is formed not 1-aminodihydro-2(1H)-pyrimidinethione (3 a) [1-aminodihydro-2-pyrimidinethiol (2 a)].

Molybdenum complexes as catalysts for the reduction of molecular nitrogen in protic media

Abstract: N2-fixing systems in protic media consisting of different reducing agents and molybdenum complexes (initially Mo(V)) as N2 activators form the same Mo(III) carbonyl upon replacing N2 by carbon monoxide. When CO is removed from the carbonyl, the Mo(III) complex formed becomes again capable of catalyzing the reduction of N2 to hydrazine by Ti(III) or Cr(II) hydroxide in aqueous alcohol. Sodium amalgam forms a particularly active system, reducting N2 catalytically in the presence of a Mo(III) complex already at room temperature.

Process for the preparation of aminotriazolobenzodiazepines

Abstract: Aminotriazolobenzodiazepines of the formulae and and their pharmacologically acceptable acid addition salts are prepared. The substituents are defined in Claim 1. The compounds of the formula VIII are obtained by reacting an appropriate phthalimide derivative with hydrazine in ethanol. The reaction product is then alkylated with an aldehyde donating the radical R' or R'' in the presence of a condensing agent. Resulting compounds having a double bond in the 5,6-position are converted into the corresponding saturated compounds by reduction with a diborane. The said compounds can be used as tranquillizers and antidepressants.

Process for preparing hydrazines

Abstract: Anhydrous hydrazine and hydrocarbyl-substituted hydrazines are efficiently prepared according to a three-step procedure, comprising a first step wherein ammonia, a primary or secondary amine, an alkali metal amide, an alkaline earth metal amide, a hydrocarbyl-substituted alkali metal amide or a hydrocarbyl-substituted alkaline earth metal amide is reacted with a chlorinating agent to produce the corresponding chloramine without co-production of an amine hydrochloride salt; a second step wherein the chloramine is reacted with a tertiary amine to produce a tertiary hydrazinium chloride; and a final step wherein the tertiary hydrazinium chloride is reacted with an alkali metal amide or an alkaline earth metal amide under anhydrous conditions to produce the desired product.

3-substituted-phenyl-6-hydrazine pyridazines

Abstract: The compounds are 3-((3-substituted amino-2-hydroxypropoxy)-phenyl)-6-hydrazino pyridazines which have β-adrenergic blocking and vasodilator activity.

Some reactions of 2-oxocyclopentanedithiocarboxylic acid and 3-methyl-5-oxo-1-phenyl-Δ2-pyrazoline-4-dithiocarboxylic acid

Abstract: The title dithiocarboxylic acids, (1) and (6) respectively, were obtained by substitution reactions of the corresponding cyclic ketones with carbon disulphide in the presence of aqueous alkali. The acid (1) reacted with hydrazine to give 1,4,5,6-tetrahydrocyclopenta[c]pyrazole-3(2H)-thione (2); the acid (6) simply afforded the hydrazide (11). Treatment of the acid (6) with aldehydes yielded the 1,3-dithietan-2-ylidenepyrazolines, (7)–(10). The acids (1) and (6) both gave benzodithiol-2-ylidene derivatives [(3), (4), and (12)] when treated with 2,4-dinitrochlorobenzene or similar reagents.

Method for increasing the lifetime of an extraction medium used for reprocessing spent nuclear fuel and/or breeder materials

Abstract: A method is provided for increasing the lifetime of an extraction medium containing an organophosphorus acid ester and a hydrocarbon and being used for reprocessing spent nuclear fuel and/or breeder materials. Impurities resulting from chemical and/or radiolytic decomposition and interfering compounds of such impurities with radionuclides are removed from the extraction medium by bringing the extraction medium, after use, into intimate contact with an aqueous hydrazine hydrate solution having a concentration of between about 0.1 molar and about 1.0 molar at a temperature between about 20° C to about 75° C. The aqueous hydrazine hydrate solution is then separated from the extraction medium.

Working up synthesis solutions obtained in production of hydrazine

Abstract: In the production of hydrazine wherein aqueous ammonia is oxidized in the presence of a ketone to form an aqueous solution containing at least one of a hydrazone and a ketazine along with ammonia, the hydrazone and ketazine are concentrated and the hydrazone and ketazine are subsequently hydrolyzed to hydrazine and ketone, the improvement which comprises effecting the concentration of the hydrazone and ketazine by extracting the aqueous solution with a substantially water-immiscible organic solvent whereby the hydrazone and ketazine preferentially enter the water-immiscible solvent, and separating the water-immiscible solvent extract from the aqueous solution. The organic solvent is preferably a higher alcohol, a chlorinated hydrocarbon, benzene or a substitution product thereof. The organic solvent extract, in one or more stages, and optionally with addition of ketone, can be re-extracted with water, hydrolyzed with aqueous acid or subjected to distillation to separate the hydrazine values from the organic solvent.

Zerovalent platinum chemistry. Part IX. Reduction of dichlorobis(phosphine)platinum(II) by hydrazine

Abstract: The isolation and characterisation of N2H-bridged complexes formed during hydrazine reduction of cis-[Pt(PR3)2Cl2] are reported. Factors affecting the stability of these new N2H complexes have been studied together with reactivity towards nucleophiles, hydrogen, and carbon monoxide.

Method for the preparation of derivatives of spiro (4,5)-decane and derivatives thus obtained

Abstract: Derivatives of spiro-(4,5)-decane, are prepared from an N-substituted-4-piperidone according to a modification of the Reformatsky reaction. The N-substituted-4-piperidone is reacted in an appropriate solvent or solvent mixture with an alpha halogen ester in the presence of activated zinc. The obtained beta-hydroxy ester is reacted with an excess of hydrazine, the resultant compound being a beta hydroxy hydrazide. The latter is subjected to a Curtius transposition with nitrous acid in excess.

Bond Scission in Sulfur Compounds. Part X. The Hydrazinolysis of Methyl p-Nitrophenyl Sulfate

Abstract: Reaction of methyl p-nitrophenyl sulfate with the hydrazine – hydrazine hydrochloride system in methanol gives rise to different types of behavior depending on the state of ionization of the reagent. For the H2NNH2/H2NNH3+ combination the observed reaction is conversion of methyl p-nitrophenyl sulfate to p-nitrophenyl sulfate ion (alkyl–oxygen scission). For the H2NNH3+/+H3NNH3+ combination, or with +H3NNH3+ alone, one observes the consecutive processes methyl p-nitrophenyl sulfate → p-nitrophenyl sulfate ion → p-nitrophenol (alkyl–oxygen followed by sulphur–oxygen scission). For the alkyl–oxygen scission process, i.e. nucleophilic displacement on the alkyl carbon, the observed pseudo first-order rate constant is given by the contributions of several nucleophilic species; A method for the dissection of kobs into the constituent terms is given. The sulphur–oxygen scission process is an acid catalyzed reaction and the measured kinetic data have been utilized for the derivation of the pKa of +H3NNH3+ in meth...