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Amines from ammonium hydroxides

Boron zirconimn chelates from ammonium hydroxide water-soluble amines sodium or potassimn zirconium and organic acid salts such as lactates, citrates, tartrates, glycolates, malates, gluconates, glycerates, and mandelates with polyols such as glycerol, erythritol, arabitol, xylitol, sorbitol, dulcitol, mannitol, inositol, monosaccharides, and disaccharides [463,464,1592,1593]... [Pg.258]

DAHA is prepared from readily available octachlorocyclotetraphosphazene. It is aminated with ammonium hydroxide in diethylether at low temperature, forming the intermediate 1,1 -diamino-3,3,5,5,7,7-hexachlorocyclotetraphosphazene. DAHA forms in the second step by nucleophilic azide displacement of the residual chloro groups with sodium azide in acetone [14, 24]. [Pg.330]

A little used synthesis of primary alkylamines is the amination of organoboranes. Organoboranes have now been shown to react with chloramine-T prepared in situ from ammonium hydroxide and sodium hypochlorite to give the corresponding amines (Scheme 5). This procedure then represents a mild, one-pot synthesis of various primary alkylamines from alkenes. [Pg.195]

Now, contrary to popular opinions, this method need not be conducted in a sealed pipe bomb. Secondary amination by substitution is as much a reaction of opportunity as it is of brute force and heat. In fact, heating can tend to cause the reformation of safrole and isosafrole. So the simplest way to do this would be to use 500mL of ammonium hydroxide or alcoholic ammonia or, for those wishing to make MDMA or meth, 40% aqueous methylamine or alcoholic methylamine (to tell you the truth, methylamine is preferable in this method because it is more reactive that ammonia so yield will increase). This 500mL is placed in a flask and into it is poured a solution of 35g bromosafrole (30g phenylisopropyl-bromide) mixed with 50mL methanol. The flask is stoppered and stirred at room temperature for anywhere from 3 to 7 days. The chemist could also reflux the same mixture for 6-12 hours or she could throw the whole mix into a sealed pipe bomb (see How to Make section) and cook it for 5 hours in a 120-130°C oil bath. [Pg.157]

The Hofmann elimination route, of which many versions exist, can be carried out at much lower temperatures in conventional equipment. The PX is generated by a 1,6-Hofmaim elimination of amine from a quaternary ammonium hydroxide in the presence of a base. This route gives yields of 17—19%. Undesired polymeric products can be as high as 80% of the product. In the presence of a polymerization inhibitor, such as phenothiazine, DPXN yields can be increased to 50%. [Pg.430]

Pentafluoroaniline. Pentafluoroaniline [771 -60-8] i2is been prepared from amination of hexafluoroben2ene with sodium amide inbquid ammonia or with ammonium hydroxide in ethanol (or water) at 167—180°C for 12—18 h. It is weakly basic (p = 0.28) and dissolves only in concentrated acids. Liquid crystals have been prepared from Schiff bases derived from pentafluoroaniline (230). [Pg.327]

Choline base [123-41 -17, [(CH2)3NCH2CH20H] 0H, triniethyl(2-hydroxyethyl)-ammonium hydroxide, derives its name from bile (Greek chole from which it was first obtained. This so-called free-ch oline is a colorless, hygroscopic Hquid with an odor of trimethyl amine. The quaternary ammonium compound (1) choline [62-49-7] or a precursor is needed in the diet as a constituent of certain phosphoHpids universally present in protoplasm. [Pg.100]

B) Preparation of 4-Amino-2-Chloro-5-(Methylsulfamyl)Benzenesulfonamide The 5-sub-stituted-2,4-dlsulfamyl anilines may be prepared by procedures described in the literature, for example, the general procedures in Monatsch. Chem. vol. 48, p 87 (1927), which involves the treatment of a m-substituted aniline with from 10 to 20 parts by weight of chlorosulfonic acid followed by the gradual addition of from about 90 to 170 parts by weight of sodium chloride. The resultant mixture is heated at approximately 150°C for about 2 hours after which the reaction mixture is poured into water and the resultant 5-substituted aniline-2,4-disulfonyl chloride is filtered and is then treated with concentrated ammonium hydroxide or suitable amine by standard procedures to obtain the corresponding disulfonamide. [Pg.1269]

The Hofmann elimination is useful synthetically for preparing alkenes since it gives the least substituted alkene. The reaction involves thermal elimination of a tertiary amine from a quaternary ammonium hydroxide these are often formed by alkylation of a primary amine with methyl iodide followed by reaction with silver oxide. The mechanism of the elimination is shown in Scheme 1.13 in this synthesis of 1-methyl-1-... [Pg.27]

A series of N-substituted narceine amides (Section III,D,1) was prepared from 101 under the action of primary amines (100). Acid-catalyzed dehydration transformed these amides to corresponding imides (ene lactams) of the ( )-narceine imide (117) type (100). Similar transformations were performed in the hydrastine series (101). JV-Methylhydrastine (98) when treated with dilute ammonium hydroxide gave hydroxy lactam 127, which was dehydrated to (Z)-fumaridine (113) (5). Sodium borohydride was able to reduce the stilbene double bond in 98 to produce saturated lactone 132 (5). [Pg.268]

The hydroxy lactams are postulated to be intermediates in transformations of enol lactones to ene lactams. This hypothesis was proved by synthesis. For example, treatment of N-methylhydrastine (98) with dilute ammonium hydroxide resulted in hydroxy lactam 148, which by the action of hydrochloric acid underwent dehydration to produce fumaridine (113) (5). Similarily, fumschleicherine (120) in reaction with trifluoroacetic acid gave fumaramine (111) 121). Narceine amide (149) was prepared from (Z)-narceine enol lactone (101) in likewise fashion 100,122) and dehydrated to narceine imide (116). A large number of N-alkylated narceine amides was synthesized from (Z)-narceine enol lactone (101) and primary amines by Czech investigators for... [Pg.276]

However, while ruthenium carbonyl was found to decompose the formate ion in basic media, the rate was slower (<0.1 mmol trimethyl ammonium formate to H2 and C02 per hour) than the rate of the water-gas shift reaction (>0.4 mmol H2/hr) at 5 atm CO and 100 °C. Increasing CO pressure decreased the formate decomposition rate. However, it was observed that increasing the CO pressure from 5 atm CO to 50 atm increased the H2 production rate to 10 mmol/hr. They proposed, in a similar manner to Pettit et al.,34 a mechanism that involved nucleophilic attack by amine (instead of hydroxide). Activation of the metal carbonyl (e.g., Ru3(CO) 2 cluster to Ru(CO)5) was suggested to be favored by dilution, increases in CO pressure, or, in the case of Group VIb metal carbonyl complexes, photolytic promotion. The mechanism is shown below in Scheme 9 ... [Pg.127]

Chapter 7 (Section C) lists the amines that have been reacted with alkoxymethylenemalonates (R3 = H). Aminomethylenemalonate (13) was prepared in 80% yield from diethyl (ethylthiomethylene)malonate with aqueous ammonium hydroxide at 0°C (52LA48). [Pg.22]

This is a general method for the preparation of alkyl thioureas. Ethylthiourea, m.p. 103-106°, has been prepared from ethyl isothiocyanate in the same manner. Di- and tri-alkyl thioureas may be prepared from alkyl isothiocyanates in a similar manner by substituting an equivalent amount of an amine solution in place of the ammonium hydroxide. Thus, sym -dimethylthiourea is prepared from methyl isothiocyanate and methylamine solution. A solution of dimethylamine and methyl isothiocyanate gives trimethylthiourea. [Pg.84]

C) dl-Phenylalanitte.—The crude bromo acid is divided into four portions and each portion is added to 2 1. of technical ammonium hydroxide (sp. gr. 0.90) in a 3-I. round-bottomed flask. The flask is well shaken, a rubber stopper is wired in, and the mixture is allowed to stand for a week. The contents of the four amination flasks (Note 5) are then combined in a 12-I. flask, 20 g. of Norite is added, and the flasks are heated on a steam cone overnight. The ammonia which is evolved is conducted into a gas-absorption trap or merely led into water by a tube from the flask. The solution is filtered while still hot on cooling most of the phenylalanine precipitates. This is filtered, washed with 250 cc. of methanol, and the filtrate evaporated under the pressure of a water pump until more crystals form. The solution is then cooled and an additional crop of phenylalanine obtained, which is also washed with methanol. The yield of crude product is 500 g., but it is slightly wet if it is dried overnight in an oven at about 8o°, it will weigh 460 g. This need not be done, however, as the yield of pure product is the same whether or not the crude product is dried. [Pg.101]

Tertiary amines do not react with nitrous acid, acetyl chloride, benzoyl chloride, benzenesulfonyl chloride, but react with alkyl halides to form quaternary ammonium halides, which are converted by silver hydroxide to quaternary ammonium hydroxides. Quaternary ammonium hydroxides upon heating yield (1) tertiary amine pins alcohol (or, for higher members, olefin plus water). Tertiary amines may also be formed (2) by alkylation of secondary amines, e.g., by dimethyl sulfate, (3) from amino acids by living organisms, e g, decomposition of fish in the case of trimethylamine. [Pg.75]

Silver hydroxide is used in exhaustive methylation, a process often utilised in order to obtain an unsaturated cyclic hydrocarbon from an amine by treating it with methyl iodide aud silver hydroxide the triniethyl-ammonium hydroxide obtained is then decomposed by distillation. [Pg.41]

Quaternary ammonium hydroxides anchored on MCM-41 provide stronger base catalysts than amine analogues11731 and were able to catalyse the same reaction as previously reported namely for the intermolecular Michael reaction leading to flavanone.[181] Moreover, this catalyst induced the successive intramolecular olefinic attack of the phenolic group from the Knoevenagel condensation product of salicylaldehyde and diethyl glutaconate (Scheme 9.6). This fast cyclization leads to chromene derivatives (1) from which subsequent conversions induced by proton abstraction from the alpha position of the ester function gives coumarin... [Pg.192]

This reaction represents the best general method for amide preparation. Cold, concentrated aqueous ammonia is used as in the preparation of iso-butyramide (83%),or the reaction may be carried out by passing dry ammonia into a solution of the acyl halide in anhydrous ether as in the formation of cyclopropanecarboxamide (91%). Separation of the amide from ammonium chloride is usually accomplished by extraction of the amide by organic solvents. Aqueous sodium hydroxide is employed to take up the hydrogen chloride when amine hydrochlorides are used in place of the free amines as in the preparation of N-methylisobutyramide (75%). When phosphorus trichloride is added to a mixture of an amine and a carboxylic acid, phosphazo compounds, RN=PNHR, rather than acyl halides, are believed to be intermediates. These compounds have been shown to react with carboxylic acids to give amides. ... [Pg.288]

The acylation of ammonia or primary and secondary amines by chloro-formic esters (chlorocarbonates) is the most general method for the synthesis of urethanes. Chlotoformates are obtained by the action of phosgene on alcohols (method 289) and, without purification, are converted to carbamates by cold concentrated ammonium hydroxide. Over-all yields from primary and secondary alcohols range from 55% to 94%. N-sub-stituted carbamates result in similar yields when primary" or secondary" amines are substituted from ammonia in the reaction. Aqueous sodium hydroxide is sometimes used to neutralize the acid formed. ... [Pg.328]


See other pages where Amines from ammonium hydroxides is mentioned: [Pg.606]    [Pg.606]    [Pg.606]    [Pg.363]    [Pg.1092]    [Pg.169]    [Pg.218]    [Pg.652]    [Pg.1092]    [Pg.727]    [Pg.64]    [Pg.64]    [Pg.725]    [Pg.247]    [Pg.379]    [Pg.216]    [Pg.207]    [Pg.71]    [Pg.1092]    [Pg.169]    [Pg.646]    [Pg.1289]    [Pg.40]    [Pg.123]    [Pg.1289]    [Pg.292]    [Pg.1777]    [Pg.738]   
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Ammonium hydroxid

Ammonium hydroxide

From aminals

From amines

From ammonium hydroxides

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