Hydrogen chloride Complex with ammonia

One of the first compounds to be introduced to the clinic, aztreonam (40-9), has been produced by total synthesis. Constmction of the chiral azetidone starts with amide formation of L-threonine (40-1) via its acid chloride treatment with ammonia leads to the corresponding amide (40-2). The primary amino group in that product is then protected as its carbobenzyloxy derivative (40-3). Reaction of that product with methanesulfonyl chloride affords the mesylate (40-4). Treatment of that intermediate with the pyridine sulfur trioxide complex leads to the formation of the A -sulfonated amide (40-5). Potassium bicarbonate is sufficiently basic to ionize the very acidic proton on the amide the resulting anion then displaces the adjacent mesylate to form the desired azetidone the product is isolated as its tetrabutyl ammonium salt (40-6). Catalytic hydrogenation over palladium removes the carbobenzyloxy protecting group to afford the free primary amine (40-7). The... 

A substantial portion of fhe gas and vapors emitted to the atmosphere in appreciable quantity from anthropogenic sources tends to be relatively simple in chemical structure carbon dioxide, carbon monoxide, sulfur dioxide, and nitric oxide from combustion processes hydrogen sulfide, ammonia, hydrogen chloride, and hydrogen fluoride from industrial processes. The solvents and gasoline fractions that evaporate are alkanes, alkenes, and aromatics with relatively simple structures. In addition, more complex... 

Ammonia a base, 184 boiling point, 64 complexes, 392, 395, 408 complex with Ag+, 154 Haber process for, 150 and hydrogen chloride, 24 model of, 21 molar volume. 60, 64 production, 150 P V behavior of, 19, 51, 60 solubility, 20 Ampere, 241 Amphoteric, 371 complexes, 396 Analogy... 

When hot, ammonia and compounds, which contain nitrogen-hydrogen bonds eg ammonium salts and cyanides react violently with chlorates and alkaline perchlorates. Diammonlum sulphate, ammonium chloride, hydroxyl-amine, hydrazine, sodamide, sodium cyanide and ammonium thiocyanate have been cited. So far as hydrazine is concerned, the danger comes from the formation of a complex with sodium or lithium perchlorate, which is explosive when ground. Many of these interactions are explosive but the factors which determine the seriousness of the accident are not known. 

The ammonia-radicle theory.—The oldest hypothesis concerning the nature of the ammonia-compounds, and that adopted by A. L. Lavoisier, supposed ammonia to be an independent base or radicle, saturating acids, and forming salts. This theory has been likened to the etherin theory of J. B. A. Dumas and P. F. G. Boullay. The radicle is NHS sal-ammoniac is NH3+HCI etc. The theory makes no attempt to explain the nature of the other classes of ammonia-compounds nor does it explain the relation of ammonia to ordinary bases, which are metallic oxides, nor the differences between the ammoniacal salts from metallic sails of the same acid. Later on, the theory became associated with the mol. compound theory, so that sal ammoniac was represented by F. A. Kekule as an associated complex of ammonia and hydrogen chloride, in which the ammonia remained tervalent. These compounds were considered to be analogous to double salts, and to substances with water of crystallization. This view was supported by the ready dissociation of sal ammoniac by heat—a subject discussed in connection with ammonium chloride (2. 20, 16). H. Rose also emphasized the analogy between compounds of ammonia and of water in various salts as exemplified by the use of the term ammonia of crystallization. 

E. D. Chattaway and H. P. Stevens found that phosphoric acid decomposes nitrogen iodide, producing ammonia. According to A. Geuther, when phosphoric acid is treated with phosphorus pentachloride at ordinary temp., phosphoryl chloride and hydrogen chloride are formed phosphorus trichloride furnishes meta-phosphoric and phosphorous acids and phosphoryl chloride is without action in the cold, but when hot, metaphosphoric acid is formed if the phosphoryl chloride be in excess, and phosphorous acid if only a little be present. G. Meyer, and A. Vogel prepared a complex with boric oxide or boric acid—vide boron phosphate, 5. 32, 27. 

The reaction between ammonia and methyl halides has been studied by using ab initio quantum-chemical methods.90 An examination of the stationary points in the reaction potential surface leads to a possible new interpretation of the detailed mechanism of this reaction in different media, hr the gas phase, the product is predicted to be a strongly hydrogen-bonded complex of alkylammonium and halide ions, in contrast to the observed formation of the free ions from reaction hr a polar solvent. Another research group has also studied the reaction between ammonia and methyl chloride.91 A quantitative analysis was made of the changes induced on the potential-energy surface by solvation and static uniform electric fields, with the help of different indexes. The indexes reveal that external perturbations yield transition states which are both electronically and structurally advanced as compared to the transition state in the gas phase. 

There have been both experimental and theoretical studies to probe the degree of concertedness in gas-phase substitutions as shown in Scheme 1. Is (2) an intermediate with a finite lifetime, or are the addition and elimination steps concerted so that (2) is a transition state Experimental molecular beam studies on the femtosecond time-scale have been reported for the reaction of chloride ions with the iodobenzene cation to yield chlorobenzene and iodine. The results show an 880 fs reaction time for the elimination process, indicating a highly non-concerted process, so that here the er-complex is an intermediate rather than a transition state.12 The reactions of halobenzene cations with ammonia have been interpreted in terms of the formation of an addition complex which may eliminate either halogen, X, or hydrogen halide, HX, depending on the nature of the halogen.13... 

Phthalocyanine complexes, deposited as a film on a metal of the same kind as their central metal ion, appeared to be active for hydrazine decomposition 48)-Wholly organic polymers, prepared by the dechlorination of poly vinylidene chloride 62> were also shown to be active, but the ammonia and hydrogen produced reacted with the catalyst, a problem also encountered with the polychelate catalysts. 

Direct methods for making the complex starting with cobalt(II) chloride involve preparation of a carbonatotetra-ammine salt by air oxidation and subsequent reaction with ammonia and hydrochloric acid. The procedure is time-consuming but gives excellent yields. A more rapid and simpler synthesis, which utihzes the reaction of hydrogen... 

Chloropentaamminecobalt(III) chloride forms red-violet rhomb-shaped crystals which decompose on heating above 150° with the stepwise loss of ammonia. The solubility of the salt in water at 25° is 0.4 g./lOO ml. The compound readily aquates in hot water, forming the aquopentaammine chloride. Chloropentaamminecobalt(III) chloride reacts with hot aqueous ethylenediamine or dZ-propylenediamine to form tris (ethylenediamine) cobalt (III) chloride or the corresponding propylenediamine compound, with liberation of ammonia. Concentrated sulfuric acid at room temperature produces a complex hydrogen sulfate of the chloro-pentaamminecobalt(III) ion. Aqueous mercury(II) chloride forms a characteristic precipitate of a double salt, [Co(NH3)6Cl]Cl2-3HgCl2, suitable for microchemical identification. Complete physical and chemical data may be found in Gmelin s handbook. ... 

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