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Ammonia treatment with

Luteocobaltic chloride (modern, [Co(NH3)6]C13, hexaamminecobalt(III) chloride) is a stable yellow-orange compound.55 In solution, all the chlorine is immediately precipitated by silver nitrate. Treatment with hydrochloric acid at 100 °C does not remove any ammonia. Treatment with sulfuric acid does not remove any ammonia, but yields the compound Co2(S04)3T2NH3, i.e. the chlorine atoms are replaced by sulfate groups. Clearly, some sort of very stable metal—ammonia bonding but much less stable metal—chlorine bonding is indicated. [Pg.7]

You have synthesized phenylalanine by the following sequence. Ethyl phenyl acetate is brominated at the a-position and then treated with ammonia. Treatment with aqueous NaOH and then acidification to pH 4 are followed by extraction with dichloromethane. You do not obtain any phenylalanine in the dichloromethane. Why not ... [Pg.1414]

The nitrochlorobenzenes are valuable dyestufTs intermediates. The presence of the nitro-groups makes the chlorine atom very reactive and easily replaceable. Treatment with ammonia or dilute alkalis substitutes an amino- or hydroxy-group for the chlorine atom and gives a series of nilroanilines and nilrophenols. [Pg.277]

Gives murexide on treatment with cone. HNOa and then ammonia. [Pg.389]

The mixture of o- and p-toluenesulplionyl chlorides produced from toluene may be separated by cooling to — 10° to — 20° when most of the p-isomer, which is a solid, m.p. 69°, separates out. Both isomers may be easily converted (e.g., by treatment with solid ammonium carbonate or with concentrated ammonia solution) into the corresponding highly crystalline siilphonamides which may be employed for Interesting syntheses. [Pg.820]

Ethyl nicotinate upon treatment with concentrated ammonia solution yields nicotinamide, which gives p-cyanopjTidine upon heating with phosphoric oxide ... [Pg.850]

The hydrogenolyaia of cyclopropane rings (C—C bond cleavage) has been described on p, 105. In syntheses of complex molecules reductive cleavage of alcohols, epoxides, and enol ethers of 5-keto esters are the most important examples, and some selectivity rules will be given. Primary alcohols are converted into tosylates much faster than secondary alcohols. The tosylate group is substituted by hydrogen upon treatment with LiAlH (W. Zorbach, 1961). Epoxides are also easily opened by LiAlH. The hydride ion attacks the less hindered carbon atom of the epoxide (H.B. Henhest, 1956). The reduction of sterically hindered enol ethers of 9-keto esters with lithium in ammonia leads to the a,/S-unsaturated ester and subsequently to the saturated ester in reasonable yields (R.M. Coates, 1970). Tributyltin hydride reduces halides to hydrocarbons stereoselectively in a free-radical chain reaction (L.W. Menapace, 1964) and reacts only slowly with C 0 and C—C double bonds (W.T. Brady, 1970 H.G. Kuivila, 1968). [Pg.114]

The dibromohydrate is first produced, and treatment with ammonia gives the free base, which after recryslallization in nitrobenzene gives brown crystals (m.p. 215°C). The picrate decomposes around 254°C. [Pg.224]

Section 1111 An example of a reaction m which the ring itself reacts is the Birch reduction The ring of an arene is reduced to a nonconjugated diene by treatment with a Group I metal (usually sodium) m liquid ammonia m the presence of an alcohol... [Pg.464]

Bromo 1 3 dimethylbenzene is inert to nucleophilic aromatic substitution on treatment with sodium amide in liquid ammonia It is recovered unchanged even after extended contact with the reagent Suggest an explanation for this lack of reactivity... [Pg.984]

Birch reduction (Section 11 11) Reduction of an aromatic nng to a 1 4 cyclohexadiene on treatment with a group I metal (Li Na K) and an alcohol in liquid ammonia Boat conformation (Section 3 7) An unstable conformation of cyclohexane depicted as... [Pg.1277]

Historically these compounds have been made in two-step processes. Eor smaller volumes, reaction of an appropriate ketone or aldehyde with a cyanide salt followed by treatment with an ammonium salt proves satisfactory (Strecker synthesis). Eor larger volumes, treatment of the ketone or aldehyde with HCN to produce a cyanohydrin, followed by treatment with ammonia has been practiced. However, in 1990, DuPont began practicing a new one-step... [Pg.221]

Rea.ctlons, As with other tertiary alcohols, esterification with carboxyUc acids is difficult and esters are prepared with anhydrides (181), acid chlorides (182), or ketene (183). Carbamic esters may be prepared by treatment with an isocyanate (184) or with phosgene followed by ammonia or an amine (185). [Pg.112]

Boron trifluoride catalyst may be recovered by distillation, chemical reactions, or a combination of these methods. Ammonia or amines are frequently added to the spent catalyst to form stable coordination compounds that can be separated from the reaction products. Subsequent treatment with sulfuric acid releases boron trifluoride. An organic compound may be added that forms an adduct more stable than that formed by the desired product and boron trifluoride. In another procedure, a fluoride is added to the reaction products to precipitate the boron trifluoride which is then released by heating. Selective solvents may also be employed in recovery procedures (see Catalysts,regeneration). [Pg.162]

Articles fabricated from FEP resins can be made bondable by surface treatment with a solution of sodium in Hquid ammonia, or naphthalenyl sodium in tetrahydrofuran (64) to faciUtate subsequent wetting. Exposing the surface to corona discharge (65) or amines at elevated temperatures in an oxidizing atmosphere (66) also makes the resins bondable. Some of the more recent work is described in References 67—69. [Pg.360]

Adberabibty of the film may be enhanced by its treatment with flame, electric discharge, boron trifluoride gas, activated gas plasma, dichromate sulfuric acid, and a solution of alkab metal ia Hquid ammonia (84—87). A coating of polyurethane, an alkyl polymethacrylate, or a chlotinated adhesive can be apphed to PVF surfaces to enhance adhesion (80,88,89). [Pg.381]

Many procedures have been studied for detoxification of aflatoxkis, including heat and treatment with ammonia, methylamine, or sodium hydroxide coupled with extraction from an acetone—hexane—water solvent system. Because ki detoxification it is important to free the toxki from cellular constituents to which it is bound, a stabifi2ation of protekis uskig a tanning compound such as acetaldehyde (qv) or glutaraldehyde may be a solution to the problem (98). [Pg.480]

Compound (12) can also be obtained by dissolving metal reactions through treatment with an excess of lithium—hquid ammonia in tert-huty alcohol (54). [Pg.253]

MAA and MMA may also be prepared via the ammoxidation of isobutylene to give meth acrylonitrile as the key intermediate. A mixture of isobutjiene, ammonia, and air are passed over a complex mixed metal oxide catalyst at elevated temperatures to give a 70—80% yield of methacrylonitrile. Suitable catalysts often include mixtures of molybdenum, bismuth, iron, and antimony, in addition to a noble metal (131—133). The meth acrylonitrile formed may then be hydrolyzed to methacrjiamide by treatment with one equivalent of sulfuric acid. The methacrjiamide can be esterified to MMA or hydrolyzed to MAA under conditions similar to those employed in the ACH process. The relatively modest yields obtainable in the ammoxidation reaction and the generation of a considerable acid waste stream combine to make this process economically less desirable than the ACH or C-4 oxidation to methacrolein processes. [Pg.253]

HydrometaHurgical Processes. The hydrometaHurgical treatments of oxide ores involve leaching with ammonia or with sulfuric acid. In the ammoniacal leaching process, the nickel oxide component of the ore first is reduced selectively. Then the ore is leached with ammonia which removes the nickel into solution, from which it is precipitated as nickel carbonate by heating. A nickel oxide product used in making steel is produced by roasting the carbonate. [Pg.3]

However, when either P(CgH )(CH2)2 or P(CgH )2(CH2) is used to form cis- or /n j -M(N2)2(PR3)4j M = Mo or W, respectively, followed by treatment with acid, ammonia yields of about 2 mol or 0.7 mol pet mole of complex for M = W and Mo, respectively, are produced (193,194). These and related data have been used to suggest a possible stepwise sequence for the reduction and protonation of N2 on a single molybdenum atom ia nitrogeaase (194). However, acidificatioa leads to complete destmctioa of the complex. Using both the stabilizing effect of the chelating phosphine triphos,... [Pg.91]

Reaction of a P-ketoestei witii gaseous ammonia (/) gives an enamine, which on treatment with methylhydiazine (2) yields an 85 15 mistuie of 3-hydioxy- and 5-hydioxy-l-substituted pyrazoles (36) (eq. 5). Previously P-ketoesters furnished mainly the 5-hydroxy isomer. [Pg.313]

Amina.tlon, 2-Antinoquinoline [580-22-3] is obtained from quinoline in 80% yield by treatment with barium amide in Hquid ammonia (19). This product, as weU as 3-aminoquinoHne [580-17-6] and 4-antino quinoline [578-68-7], maybe obtained through nucleophilic substitution of the corresponding chloroquinolines with ammonia. [Pg.389]

Silver Chloride. Silver chloride, AgCl, is a white precipitate that forms when chloride ion is added to a silver nitrate solution. The order of solubility of the three silver halides is Cl" > Br" > I. Because of the formation of complexes, silver chloride is soluble in solutions containing excess chloride and in solutions of cyanide, thiosulfate, and ammonia. Silver chloride is insoluble in nitric and dilute sulfuric acid. Treatment with concentrated sulfuric acid gives silver sulfate. [Pg.89]

Reduction and Hydrodesulfurization. Reduction of thiophene to 2,3- and 2,5-dihydrothiophene and ultimately tetrahydrothiophene can be achieved by treatment with sodium metal—alcohol or ammonia. Hydrogen with Pd, Co, Mo, and Rh catalysts also reduces thiophene to tetrahydrothiophene [110-01-0] a malodorous material used as a gas odorant. [Pg.20]

Conversion to cellulose II and cellulose III via caustic mercerization and Hquid ammonia treatment are commercial textile processes that are discussed later. Figure 7 shows the characteristic diffractograms (CuKa radiation) of native cellulose, cellulose mercerized with sodium hydroxide, and cellulose treated with Hquid ammonia. [Pg.313]


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See also in sourсe #XX -- [ Pg.189 , Pg.223 ]




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