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Formamides halogen

Incompatible with ethanol, ethanol + butadiene, ethanol + phosphorus, ethanol + methanol + HgO, formamide + pyridine + sulfur trioxide, formamide, halogens or interhalogens (e.g., chlorine), mercuric oxide, metals (e.g., aluminum, lithium, magnesium), metal carbides (e.g., lithium carbide, zirconium carbide), oxygen, pyridine, sodium hydride, sulfides. [Pg.772]

IODINE (7553-56-2) A powerful oxidizer. Material or vapors react violently with reducing agents, combustible materials, alkali metals, acetylene, acetaldehyde, antimony, boron, bromine pentafluoride, bromine trifluoride, calcium hydride, cesium, cesium oxide, chlorine trifluoride, copper hydride, dipropylmercury, fluoride, francium, lithium, metal acetylides, metal carbides, nickel monoxide, nitryl fluoride, perchloryl perchlorate, polyacetylene, powdered metals, rubidium, phosphorus, sodium, sodium phosphinate, sulfur, sulfur trioxide, tetraamine, trioxygen difluoride. Forms heat- or shock-sensitive compounds with ammonia, silver azide, potassium, sodium, oxygen difluoride. Incompatible with aluminum-titanium alloy, barium acetylide, ethanol, formamide, halogens, mercmic oxide, mercurous chloride, oxygen, pyridine, pyrogallic acid, salicylic acid sodium hydride, sodium salicylate, sulfides, and other materials. [Pg.658]

A derivative of an isomeric azapurine ring system interestingly exhibits bronchodilator activity, possibly indicating interaction with a target for theophylline. The starting pyridazine 97 is available from dichloro compound 96 by sequential replacement of the halogens. Treatment of 97 with formic acid supplies the missing carbon and cyclizes the intermediate formamide with consequent formation of zindotrine (98) [16]. [Pg.168]

Aldehydes, formates, primary, and secondary alcohols, amines, ethers, alkyl halides, compounds of the type Z—CH2—Z, and a few other compounds add to double bonds in the presence of free-radical initiators/ This is formally the addition of RH to a double bond, but the R is not just any carbon but one connected to an oxygen or a nitrogen, a halogen, or to two Z groups (defined as on p. 548). The addition of aldehydes is illustrated above. Formates and formamides " add similarly ... [Pg.1034]

Ethyl sulfate Flammable liquids Fluorine Formamide Freon 113 Glycerol Oxidizing materials, water Ammonium nitrate, chromic acid, the halogens, hydrogen peroxide, nitric acid Isolate from everything only lead and nickel resist prolonged attack Iodine, pyridine, sulfur trioxide Aluminum, barium, lithium, samarium, NaK alloy, titanium Acetic anhydride, hypochlorites, chromium(VI) oxide, perchlorates, alkali peroxides, sodium hydride... [Pg.1477]

Statt der a-Halogen-ketone konnen auch a-Halogen-0,0-acetale eingesetzt werden. So erhalt man aus 2-Brom-l,l-dimethoxy-ethan mit Formamid unter Durchleiten von Ammoniak-Gas Imidazol in 50% Ausbeute51 ... [Pg.17]

The starting material (48-1) for a pyrrazolopyridazine can be obtained by treating the corresponding enol, which is simply the condensation product of methylmaleic anhydride and hydrazine, with phosphorus oxychloride. Reaction with piperazine leads to the displacement of the sterically more accessible chlorine to afford the alkylation product (48-2). Treatment with hydrazine leads to the replacement of the remaining halogen and the formation of (48-3). The missing carbon is, in this case, supplied by formamide to afford zindotrine (48-4) [51], a compound that shows activity as a bronchodilator. [Pg.609]

Their utility has been demonstrated in various Friedel-Crafts reactions,44-47 halogen addition,48 49 electrophilic nitration of aromatics,50 and various hydrogenation processes51-53 including the Ru-catalyzed hydrogenation of C02 to /V,/V-dipropyl formamide in supercritical C02 under biphasic conditions 54 The use of in situ IR spectroscopy allowed Horvath and coworkers to demonstrate that the same substrate-catalyst and product-catalyst complexes are produced in Friedel-Crafts acetylation of benzene in ionic liquids as in CH2C12 55... [Pg.810]

Low molecular weight aromatic ethers have been prepared principally by the condensation of phenolate salts with aromatic halides 82). The Ullmann condensation (81), which employs copper or its salts as catalysts has been used in most cases in the laboratory. Recently a modification of the Ullmann condensation which consists of heating copper (1) oxide, the free phenol, and the aromatic halide in s-collidine has been reported (3). This method is recommended for alkali-sensitive aromatic compounds. In addition, reaction of phenolate salts with copper (1) oxide and the aromatic halide in boiling N,N-dimethyl formamide is described. When the halogen is activated by electronegative groups as in -chloroni-... [Pg.496]

The compound [Ph4As][Pt(CO)Cl3] is characterized by IR absorption at 2077 cm 1 (Nujol) and 2095 cm 1 in dichloromethane. Yellow crystals of the compound decompose in air at 179°C. The compound is unreactive in air, but decomposes slowly in water. It is soluble in dichloromethane and dimethyl-formamide, slightly soluble in ethanol, and insoluble in water, diethyl ether, and hexane. The chlorine ligand trans to the CO is readily displaced by other halogens and other ligands.6 The compound reacts with chlorine to form [Pt(CO)Cl5]-.7... [Pg.245]

Solvatochromic Approach Solvatochromic relationships are multivariate correlations between a property, usually solubility or partitioning property (see Sections 11.4 and 13.3), and solvatochromic parameters, parameters that account for the solutes interaction with the solvent. In the case of vapor pressure, the solvatochromic parameters only have to account for intermolecular interaction such as selfassociation between the solute (i.e., pure compound) molecules themselves. The following model has been reported for liquid and solid compounds, including hydrocarbons, halogenated hydrocarbons, alkanols, dialkyl ethers, and compounds such as dimethyl formamide, dimethylacetamide, pyridine, and dimethyl sulfoxide... [Pg.78]

The reactivity of halogen atoms in position 2 of oxazoles is considerably enhanced by quaternization. This is best illustrated by the synthetic utility of the salt (141) which, like other Ar-alkyl-2-halogeno-azolium and -azinium salts, effects a number of condensation reactions but it far surpasses these other salts in activity (79AG(E)707). Thus it activates carboxylic acids and it dehydrates formamides to isocyanides (Scheme 6). Amides are similarly converted into cyanides, ketones (RCH2COAr) into alkynes (RC=CAr), and cyanohydrins (RCH(OH)CN) are transformed into the corresponding chloro compounds <79CL1117>. [Pg.193]

X = halogen, OH, NH2, or -OCOR". As the applicability of this method to the synthesis of 2-substituted imidazoles depends on the use of amides other than formamide, limitations have been imposed on the procedure, although various 2-methylimidazoles have been... [Pg.113]

Imidazole, itself, is prepared in 60% yield from the reaction of bromoacetaldehyde (as the glycol acetal), formamide, and ammonia at 180°C.70 The initial step in the formation of imidazoles from a-haloketones is replacement of the halogen by an hydroxy group.65 From the stage of acyloin formation it is assumed 61 that the following reaction path is followed ... [Pg.114]


See other pages where Formamides halogen is mentioned: [Pg.587]    [Pg.657]    [Pg.658]    [Pg.682]    [Pg.679]    [Pg.255]    [Pg.253]    [Pg.587]    [Pg.657]    [Pg.658]    [Pg.682]    [Pg.679]    [Pg.255]    [Pg.253]    [Pg.230]    [Pg.275]    [Pg.42]    [Pg.380]    [Pg.102]    [Pg.132]    [Pg.399]    [Pg.15]    [Pg.16]    [Pg.48]    [Pg.263]    [Pg.326]    [Pg.481]    [Pg.602]    [Pg.608]    [Pg.325]    [Pg.523]    [Pg.105]    [Pg.1157]    [Pg.82]    [Pg.33]    [Pg.275]    [Pg.1157]    [Pg.572]   
See also in sourсe #XX -- [ Pg.24 , Pg.491 ]




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Formamide

Formamides

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