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And hydrazine

Copper(l) oxide, CujO. Red solid formed from Cu(II) salt and hydrazine or heat on CuO. Gives a cheap red glass and a cuprate, KCuO (K2O plus CU2O). [Pg.112]

The majority of practical micellar systems of Tionnal micelles use water as tire main solvent. Reverse micelles use water immiscible organic solvents, altlrough tire cores of reverse micelles are usually hydrated and may contain considerable quantities of water. Polar solvents such as glycerol, etlrylene glycol, fonnamide and hydrazine are now being used instead of water to support regular micelles [10]. Critical fluids such as critical carbon dioxide are... [Pg.2575]

It must be noted, however, that nitroso, azoxy and azo compounds when subjected to the same treatment yield res])ectively hydroxylamines, hydrazo and hydrazine compounds, all of which reduce ammoniacal silver nitrate solution in the cold. [Pg.528]

Dimethylpyrazole (III) may be prepared from acetylacetone (I) and hydrazine (II) (produced from hydrazine sulphate and aqueous alkali). The reaction may be represented as ... [Pg.842]

The principal reactions of this class of compounds are summarized in Scheme 172. In most of these reactions the reactive nucleophilic center is the terminal NHj group, although the other exocyclic nitrogen may also be involved, as shown by acetylation, which yields 284 and 285. However, the structure of compound 281 is not the one proposed in a recent report (1582) that attributes the attack to the other exocyclic nitrogen. The formation of osazones (287) from sugars, 2-hydrazinothiazoles, and hydrazine has been reported (525, 531). [Pg.100]

The reactor effluent, containing 1—2% hydrazine, ammonia, sodium chloride, and water, is preheated and sent to the ammonia recovery system, which consists of two columns. In the first column, ammonia goes overhead under pressure and recycles to the anhydrous ammonia storage tank. In the second column, some water and final traces of ammonia are removed overhead. The bottoms from this column, consisting of water, sodium chloride, and hydrazine, are sent to an evaporating crystallizer where sodium chloride (and the slight excess of sodium hydroxide) is removed from the system as a soHd. Vapors from the crystallizer flow to the hydrate column where water is removed overhead. The bottom stream from this column is close to the hydrazine—water azeotrope composition. Standard materials of constmction may be used for handling chlorine, caustic, and sodium hypochlorite. For all surfaces in contact with hydrazine, however, the preferred material of constmction is 304 L stainless steel. [Pg.282]

Anhydrous hydrazine, required for propellant appHcations and some chemical syntheses, is made by breaking the hydrazine—water azeotrope with aniline. The bottom stream from the hydrate column (Fig. 4) is fed along with aniline to the azeotrope column. The overhead aniline—water vapor condenses and phase separates. The lower aniline layer returns to the column as reflux. The water layer, contaminated with a small amount of aniline and hydrazine, flows to a biological treatment pond. The bottoms from the azeotrope column consist of aniline and hydrazine. These are separated in the final hydrazine column to give an anhydrous overhead the aniline from the bottom is recycled to the azeotrope column. [Pg.282]

By fai the largest (ca 85% of the total) volume chemical blowing agent is azodicaibonamide (44), made by the oxidation of hydiazodicaiboxamide [110-21 -4] (51) using chlorine or sodium chlorate. The hydrazo precursor is made by refluxing an aqueous solution of urea and hydrazine (172) ... [Pg.289]

The tiiazole [288-88-OJ (56) lequked foi these products can be made from formamide and hydrazine (182,183) ... [Pg.290]

Group 15 (VA) Perchlorates. Nitrogen perchlorates have been used as oxidizers in rocket propellants. Hydrazine perchlorate [13762-80-6] NH2NH2CIO4, and hydrazine diperchlorate, CIO4NH2NH2CIO4, have been investigated as oxidizers for propellant systems (60). Anhydrous salts can be... [Pg.66]

For once-through boilers, the treatment must be without soHd residues, so all-volatile treatment (AVT) is used. AVT, which is also used in some dmm boiler systems, rehes on the feedwater chemical additives, ammonia and hydrazine, to provide water appropriate to the boiler. Because the additives are volatile, they do not accumulate in the boiler and provide only minimal protection during contaminant ingress. Most plants using AVT have some form of condensate poHsher to remove impurities from the condensate. [Pg.362]

Supercritial boilers use all-volatile treatments, generally consisting of ammonia and hydrazine. Because of the extreme potential for deposit formation and steam contamination, no soHds can be tolerated in supercritical once-through boiler water, including treatment soHds. [Pg.264]

Unit cells of pure cellulose fall into five different classes, I—IV and x. This organization, with recent subclasses, is used here, but Cellulose x is not discussed because there has been no recent work on it. Crystalline complexes with alkaU (50), water (51), or amines (ethylenediamine, diaminopropane, and hydrazine) (52), and crystalline cellulose derivatives also exist. Those stmctures provide models for the interactions of various agents with cellulose, as well as additional information on the cellulose backbone itself. Usually, as shown in Eigure la, there are two residues in the repeated distance. However, in one of the alkah complexes (53), the backbone takes a three-fold hehcal shape. Nitrocellulose [9004-70-0] heUces have 2.5 residues per turn, with the repeat observed after two turns (54). [Pg.240]

Organic solutions of HOCl can be prepared in near quantitative yield (98—99%) by extraction of CU -containing aqueous solutions of HOCl with polar solvents such as ketones, nitriles, and esters (131). These organic solutions of HOCl have been used to prepare chlorohydrins (132) and are especially useful for preparation of water-insoluble chlorohydrins. Hypochlorous acid in methyl ethyl ketone has also been used to prepare Ca(OCl)2, by reaction with CaO or Ca(OH)2 (133), and hydrazine by reaction with NH3 (134). [Pg.468]

Pyridazinecarbohydrazides are prepared in the normal way from an ester or acid chloride and hydrazine or a substituted hydrazine, generally in good yields. Pyridazines with two ortho alkoxycarbonyl groups give cyclic hydrazides with hydrazine, which are pyridazinopyridazines. [Pg.34]

Phthalic anhydride and diethyl phthalate are easily converted with hydrazine into 4-hydroxyphthalazin-l(2/f)-one. Its substituted derivatives have been prepared using substituted hydrazines, substituted phthalic anhydrides, or diesters or disodium salts of substituted phthalic acids (Scheme 81). However, condensation of phenylhydrazine with phthalic anhydride gives only a small amount of the corresponding phthalazine, the main product being 2-anilinophthalimide. This can be rearranged in the presence of base into the phthalazine derivative. For the preparation of 2,3-disubstituted derivatives, 1,2-disub-stituted hydrazines are reacted with the appropriate phthalic anhydrides or phthaloyl chlorides. Derivatives of 4-amino- or 4-hydrazino-phthalazin-l(2iT)-one have been prepared either from the corresponding monothiophthalimide and 3-aminoisoindolin-3-one (1S4) or from ethyl 2-cyanobenzoate (155) and hydrazine hydrate (Scheme 82). Similarly,... [Pg.47]

The most useful syntheses of pyridazines and their alkyl and other derivatives begins with the reaction between maleic anhydride and hydrazine to give maleic hydrazide. This is further transformed into 3,6-dichloropyridazine which is amenable to nucleophilic substitution of one or both halogen atoms alternatively, the halogen(s) can be replaced by hydrogen as shown in Scheme 110. In this manner a great number of pyridazine derivatives are prepared. [Pg.55]

Hydroxyphthalazin-l(2//)-one is obtained in a smooth reaction between phthalic anhydride and hydrazine hydrate and this is again the starting compound for many 1-substituted and/or 1,4-disubstituted phthalazines. The transformations of 1,4-dichloro-phthalazine, which is prepared in the usual manner, follow a similar pattern as shown for pyridazines in Scheme 110. On the other hand, phthalonitrile is the preferential starting compound for amino- and hydrazino-phthalazines. The most satisfactory synthesis of phthalazine is the reaction between a,a,a, a -tetrachloro-o-xylene and hydrazine sulfate in sulfuric acid (67FRP1438827), alt iough catalytic dehalogenation of 1-chloro- or 1,4-dichloro-phthalazine or oxidation of 1-hydrazinophthalazine also provides the parent compound in moderate yield. [Pg.56]

The Msz group is stable to TFA/anisole, NaOH, and hydrazine. Formation... [Pg.340]

Triazole has been prepared by the oxidation of substituted 1,2,4-triazoles, by the treatment of urazole with phosphorus pentasulfide, by heating equimolar quantities of formyl-hydrazine and formamide, by removal of the amino function of 4-amino-l,2,4-triazole, by oxidation of l,2,4-triazole-3(5)-thiol with hydrogen peroxide, by decarboxylation of 1,2,4-triazole-3(5)-carboxylic acid, by heating hydrazine salts with form-amide,by rapidly distilling hydrazine hydrate mixed with two molar equivalents of formamide, i by heating N,N -diformyl-hydrazine with excess ammonia in an autoclave at 200° for 24 hours, and by the reaction of 1,3,5-triazine and hydrazine monohydrochloride. ... [Pg.102]

In the case of boilers operating at low pressure, organic materials such as natural and modified tannins, starches, or alginates are added to aid blowdown. For boilers operating at high pressure, synthetic materials such as polyacrylates and polymethacrylates have been developed. The most commonly used chemicals for boiler feedwater treatment are phosphates and hydrazine. [Pg.155]


See other pages where And hydrazine is mentioned: [Pg.48]    [Pg.139]    [Pg.142]    [Pg.207]    [Pg.208]    [Pg.8]    [Pg.93]    [Pg.292]    [Pg.92]    [Pg.456]    [Pg.390]    [Pg.263]    [Pg.196]    [Pg.419]    [Pg.52]    [Pg.52]    [Pg.73]    [Pg.209]    [Pg.291]    [Pg.118]    [Pg.157]    [Pg.278]    [Pg.139]    [Pg.204]    [Pg.346]    [Pg.74]   
See also in sourсe #XX -- [ Pg.111 ]




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AZINES AND HYDRAZINES

Addition Reactions using Iminium Ions Derived from Hydrazines, Hydroxylamines and Sulfinamides

Azides via nitrosation of hydrazines and hydrazides

Condensation of benzaldehyde and hydrazine

Condensation, of acetoacetic ester, acid with sodium cyanide and hydrazine

Condensations with Hydroxylamine and Hydrazines

Conformations of Hydrazine and Hydrogen Peroxide

Cyclic hydrazines and hydrazones

Determination of Hydrazine and Its Derivatives

Diimide, and Hydrazine Complexes of Platinum

Ethyl hydrazinecarboxylate from hydrazine hydrate and

Ethyl hydrazinecarboxylate, from hydrazine hydrate and diethyl

Ethyl hydrazinecarboxylate, from hydrazine hydrate and diethyl carbonate

Fluorofunctional Silylamines and -Hydrazines

HYDRAZINE AND ITS DERIVATIVES

HYDRAZINE METAL MALONATES AND

HYDRAZINE METAL MALONATES AND SUCCINATES

Hydrazination, hydrazines and

Hydrazination, hydrazines and

Hydrazine and derivatives

Hydrazine and its Salts

Hydrazine and methylhydrazines

Hydrazine and nitro

Hydrazine and ring

Hydrazine perchlorate and chlorate complexes

Hydrazine with aldehydes and

Hydrazine with aldehydes and ketones

Hydrazine, Azide, Hydroxylamine, and Derivatives

Hydrazine, Azides, Hydroxylamines, and Derivatives

Hydrazine, Hydrogen Peroxide, and Related Hydrides

Hydrazine-mono- and -bisborane

Hydrazines and Amines

Hydrazines and hydrazones

Hydrazines and their Derivatives

Hydrazines via reduction of diazo compounds and diazonium

Hydrazines, Hydrazones and Related Compounds

Hydrazines, Hydrazones, Osazones, and Derived Heterocycles

Hydroxylamine and hydrazine

Hydroxylamine, hydrazine, hydrazoic acid and azide ion

Inorganic Hydrazine Derivatives: Synthesis, Properties and Applications, First Edition

Plasma-Chemical Hydrazine (N2H4) Synthesis from Nitrogen and Hydrogen in Non-Equilibrium Discharges

Polarography and reactions with hydrazine

Pyrazoles by a Consecutive 3CR of (Hetero)aryl Halides, Propargyl Alcohols, and Hydrazines

Reaction With Hydrazine, Secondary, and Tertiary Amines

Reaction of phenols with ammonia, amines, and hydrazines

Reactions of Hydrazine and Hydroxylamine

Reactions of Hydrazines and Hydroxylamines

Reactions of phosgene with ammonia and hydrazine

Reduction of azines, hydrazones, hydrazines, and hydrazides

Sodium Azide, Plant Analytical Procedures Hydrazine and Ethyl Nitrate

Structure and performance of hydrazine-containing polyurethane thermoplastic elastomers

Synthesis and properties of polyurethane thermoplastic elastomers comprising hydrazine derivatives

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