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Ureas amines

Important applications for titanium have been developed in processes involving acetic acid, malic acid, amines, urea, terephthalic acid, vinyl acetate, and ethylene dichloride. Some of these represent large scale use of the material in the form of pipework, heat exchangers, pumps, valves, and vessels of solid, loose lined, or explosion clad construction. In many of these the requirement for titanium is because of corrosion problems arising from the organic chemicals in the process, the use of seawater or polluted cooling waters, or from complex aggressive catalysts in the reaction. [Pg.875]

One of the major constituents of urine is the di-amine, urea (III). Each amine group in urea should remind us of ammonia in Equation (6.11). Solutions of urea in water are basic because the two amine moieties each abstract a proton from water, to generate an ammonium salt and a hydroxide ion ... [Pg.243]

A)Double-base, solventless proplnt is prepd by blending, under water a mixt of NC 65, DEGDN 28, w-tnsol soap (Ca oleate 70, Mg oleate 18. Ca stearate 12%) 5 and a product obtd by treating oleic (or stearic) acid with alpha-naphthyl amine urea 2%. The resulting slurry is centrifuged (to remove all but 30% of w)... [Pg.185]

The common initial products of the rearrangements are isocyanates, which readily react with all types of compounds containing—OH, —NH or —SH functions, giving amines, ureas, urethanes, thioure-thanes, amides etc. (Scheme 2). Isolation of the isocyanates may be possible under some reaction conditions, especially in the Curtius reaction when the rearrangement is conducted in aptotic solvents, but usually the solvolytic conversion of isocyanates occurs to give amines or ureas. [Pg.796]

Properties Colorless liquid when very pure, becomes reddish-brown on exposure to light and air odor somewhat similar to benzaldehyde. Forms condensation products with many types of compounds, phenol, amines, urea, etc. D 1.1598 (20/4C), fp —36.5C, bp 161.7C, heat of vaporization 107.5 cal, refr index 1.5260 (20C), flash p 140F (60C) (CC), autoign temp 392C (797F). Soluble in alcohol, ether, and benzene 8.3% soluble in water at 20C. Combustible. [Pg.588]

WateH Organotin, f-amine Urea, carbon dioxide... [Pg.687]

CP/MAS NMR. In the first of these papers the structures within the resins were examined as a function of cure temperature [17]. The chemistry of the resins is very complex but one of the principle reactions is the formation of stable isocyanurate structures from three isocyanate units. Other species are also present e.g., amine, urea and biuret. These are formed by the reactions shown in Fig. 15.2.13. CP/MAS NMR spectra of the resins indicated that the optimum cure temperature was 120°C at which most of the isocyanate groups were converted to isoeyanurate (Fig. 15.2.14). [Pg.523]

The first application of natural-abundance solid state 15NNMR was on the complex solids from the reaction of hydrogen cyanide and ammonia. Signals in the solid state spectrum of the cold water soluble fraction are attributed to the NH4 salt, amine-, urea-, peptide-, nitrile-, and pyrrole-like nitrogens. The spectrum of the cold water insoluble fraction shows two broad resonances indicating a diversity of nitrogen functionality, possibly including crosslinked aromatics and purine-like compounds (3). [Pg.219]

Cyclooctyl amine, urea and dimethylamine are reacted in a two-step reaction ... [Pg.655]

ISOCYANURIC CHLORIDE (87-90-1) A powerful oxidizer. Violent reaction with reducing agents. Reacts with acrolein, antimony trisulfide, antimony tritelluride, arsenic pentasul-fide, 1,1-dichloro-l-nitroethane, 1,3-dichloropropene, diethylamine, s-trioxane. Incompatible with m-bis(trichlormethyl)benzene. Reacts with nitrogen-containing compounds ammonia, amines, urea, forming the unstable explosive nitrogen trichloride. Contact with combustible material, organic substances may cause fire. [Pg.668]

In a study covering a wide range of polar and acidic pesticides deethylatrazine and atrazine besides anilide, phenoxy acid, phenylurea, carbamates and other types of specific pesticides in river water were determined by ESI-LC-MS and MS/MS. Recoveries, depending on preconcentration steps, obtained with different SPE materials (PLRS-S, Hyshere-1, LiChrolut EN and Isolute ENV -i-) and at different pH values were reported [502]. Sixteen of the most widely used pesticides in Southern Italy were monitored in surface water samples taken in the Calabria region. Triazines were determined quantitatively by LC-UV and ESI-LC-MS(-i-) and were confirmed by MS [537]. In another study the simultaneous determination of 26 non-acidic (base and neutral e.g. triazine, carbamate, anilide, N-substituted amine, urea and organophosphorus type) and 13 acidic (sulfuron and phenoxy acid type) pesticides in natural waters was performed using ESI-LC-MS. Recoveries... [Pg.820]

This reaction was first reported by Lossen in 1872. It is a thermal or alkaline conversion of hydroxamic acid into an isocyanate via the intermediacy of its O-acyl, sulfonyl, or phosphoryl derivative. In the presence of water, amine, or alcohol, the isocyanate is converted into amine, urea or urethane, respectively. Therefore, this reaction is generally known as the Lossen rearrangement. Occasionally, it is also referred to as the Lossen reaction, Lossen degradation, or Lossen transformation. ... [Pg.1772]

This reaction has general application in the preparation of amine, urea, and urethane derivatives. [Pg.1774]

Uses As chemicai intermediates in the prod, of drugs, pesticides, amines, ureas, carbamoyl compds. [Pg.896]


See other pages where Ureas amines is mentioned: [Pg.234]    [Pg.246]    [Pg.747]    [Pg.235]    [Pg.4017]    [Pg.2100]    [Pg.402]    [Pg.502]    [Pg.503]    [Pg.512]    [Pg.116]    [Pg.724]    [Pg.428]    [Pg.1175]    [Pg.1175]    [Pg.1180]    [Pg.1181]    [Pg.1181]    [Pg.981]    [Pg.151]    [Pg.662]    [Pg.693]    [Pg.877]    [Pg.163]    [Pg.626]    [Pg.627]    [Pg.1130]   
See also in sourсe #XX -- [ Pg.868 ]




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Alkyl, amines ureas

Amine/urea catalysts

Bifunctional Tertiary Amine Thio(ureas)

N Monosubstituted ureas from primary amines and silicon tetraisocyan

N-Monosubstituted ureas from primary amines and silicon tetraisocyanate

Primary amine- urea-mediated

Primary amine- urea-mediated reactions

Primary amines urea derivatives

Urea tertiary amine-functionalized

Urea-amine bifunctional catalyst

Urea-amine bifunctional catalyst reaction

Ureas (s. a. Iminoureas amines

Ureas amines and carbon monoxid

Ureas from amines

Ureas from amines and

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