Ammonia from amines

Teter et al. filed a series of patents aimed at the production of organic compounds containing nitrogerf or the production of nitriles and amines from ammonia and olefins by passing mixtures of olefin and NH3 over transition metals, mainly cobalt deposited on various supports at 250-370°C and 100-200 bar [27- 3]. With cobalt on asbestos, a mixture of amine, nitrile, olefin hydrogenation product, polymers, and cracking products is obtained (Eq. 4.1) [31]. 

It is possible to synthesise this species as complexes with one equivalent of a variety of amines, from ammonia to quinoline. The complexes are storable at room temperature but highly explosive on heating or under mechanical shock. The antimony analogues are similar. 

Stallman reported production of diglycidyl amines from ammonia and epichlorohydrin. 

This hydroaminomethylation has only been applied in homogeneous one-phase systems until now. The reaction will mostly lead to secondary and tertiary amines, because the intermediate primary amines will further react with the aldehyde formed to secondary amines. The synthesis of the technically important primary amines from ammonia and alkenes via hydroaminomethylation was investigated, but only low selectivities (32 %) and TOFs (9 h ) to primary amines could be achieved, despite the high excess of ammonia. Other side products, e. g., via aldo-lization, are also observed. 

The advantages in this reaction lie in economy and simplicity however long reaction times, sealed tube conditions, and high temperatures remain major drawbacks. In addition, formation of the //-formyl derivative is frequently seen, and the selective synthesis of a primary amine from ammonia is difficult.3,4... 

Allylation of ammonia gives a mixture of products, and it is difficult to prepare primary amines from ammonia, and several ammonia surrogates are used. Allylation of sodium diformylamide (219) with the allyl acetate 218 proceeded smoothly by using DPPF as a ligand to afford 220, which was hydrolyzed to provide the primary allylamine 221. The reaction was sluggish when PPhs was used. The primary allylamine 224 with high ee (95.5 %) was obtained from 94 via 223 by the use of (5)-BINAP [81]. 

Judicious selection of catalyst is necessary to avoid multi-allqrlation ruthenium catalysts tend to provide primary amines from ammonia, while iridium catalysts tend to provide seeondary or tertiary amines (Scheme 12.3). The reasons for the mono-allqrlation seleetivity of ruthenium catalysts have not been thoroughly studied however, Vogt reports that extended reaction times aetually increase the seleetivity for primary amine formation. This observation points toward the reversibility of secondary imine formation, wherein hydrolysis of the seeondary imine is favoured over hydrogenation to the seeondary amine. Both iridium and ruthenium catalysts have proven to be effeetive with aqueous ammonia. 

Primary amines form Schiff bases, (CH3 )2C=NR. Ammonia induces an aldol condensation followed by 1,4-addition of ammonia to produce diacetone amine (from mesityl oxide), 4-amino-4-methyl-2-pentanone [625-04-7] (CH2)2C(NH2)CH2COCH2, and triacetone amine (from phorone),... 

In practice, ammonia is most frequendy used. With hexa, the initial reaction steps differ, but the final resole resins are identical, provided they contain the same number of nitrogen and CH2 groups. Most nitrogen from ammonia or hexa is incorporated as diben2ylamine with primary, tertiary, and cycHc amine stmctures as minor products. 

Batch or continuous processes can be used to prepare tertiary amines from alcohols and ammonia or a secondary amine, such as, dimethylamine. 

Ammonia is used in the fibers and plastic industry as the source of nitrogen for the production of caprolactam, the monomer for nylon 6. Oxidation of propylene with ammonia gives acrylonitrile (qv), used for the manufacture of acryHc fibers, resins, and elastomers. Hexamethylenetetramine (HMTA), produced from ammonia and formaldehyde, is used in the manufacture of phenoHc thermosetting resins (see Phenolic resins). Toluene 2,4-cHisocyanate (TDI), employed in the production of polyurethane foam, indirectly consumes ammonia because nitric acid is a raw material in the TDI manufacturing process (see Amines Isocyanates). Urea, which is produced from ammonia, is used in the manufacture of urea—formaldehyde synthetic resins (see Amino resins). Melamine is produced by polymerization of dicyanodiamine and high pressure, high temperature pyrolysis of urea, both in the presence of ammonia (see Cyanamides). 

Succinic acid reacts with urea in aqeous solution to give a 2 1 compound having mp 141°C (116,117), which has low solubiUty in water. A method for the recovery of succinic acid from the wastes from adipic acid manufacture is based on this reaction (118,119). The monoamide succinamic acid [638-32-4] NH2COCH2CH2COOH, is obtained from ammonia and the anhydride or by partial hydrolysis of succinknide. The diamide succinamide [110-14-3], (CH2C0NH2)2, nip 268—270°C, is obtained from succinyl chloride and ammonia or by partial hydrolysis of succinonitrile. Heating succinknide with a primary amine gives A/-alkylsucckiknides (eq. 9). 

The reaction can be driven to the tetraalkoxide stage by addition of an amine or ammonia to scavenge the Hberated hydrochloric acid. The amine or ammonium hydrochloride that forms can be filtered from the reaction mass and the tetraalkyl titanate purified by distillation. If the reaction is mn in the starting alcohol as solvent, the chloride salts formed are in a finely divided state and difficult to filter. When the reaction is mn in the presence of an inert hydrocarbon solvent such as heptane or toluene, a much more readily filterable salt is obtained. The solution of cmde tetraalkyl titanate can be distilled to remove solvent and give a pure product (1,2). 

Zirconium tetrachloride is instantly hydrolyzed in water to zirconium oxide dichloride octahydrate [13520-92-8]. Zirconium tetrachloride exchanges chlorine for 0x0 bonds in the reaction with hydroxylic ligands, forming alkoxides from alcohols (see Alkoxides, METAl). Zirconium tetrachloride combines with many Lewis bases such as dimethyl sulfoxide, phosphoms oxychloride and amines including ammonia, ethers, and ketones. The zirconium organometalLic compounds ate all derived from zirconium tetrachloride. 

Apart from ammonia, other breakdown products include primary amines and hydroxylamines, which may be corrosive to cuprous metals, and various organic acids that may be corrosive to ferrous metals and turbine blades. These organic acids also neutralize any remaining... 

Amines are derived from ammonia by the replacement of hydrogen atoms with organic groups. Amides result from the condensation of amines with carboxylic acids. Amines and many amides take part in hydrogen bonding. 

OH group has been replaced by an amino group or a substituted amino group. An amide contains the group —CONR,. Example CH.CONIL, acetamide, amine A compound derived from ammonia by... 

This fluorescent acid chloride can be used to form derivatives of alcohols, amines, and phenols. Using these fluorescent derivatives, an analysis of a series of n-alcohols from Ci to C4 was developed. A chromatogram produced by this technique is shown in Figure 3. Derivatives were also formed from ammonia, dimethylamine, and phenol. A derivative was formed from pentachlorophenol but was not fully characterized. The quantum yields of fluorescence of the alcohol derivatives of V were lower than those of the alkyl halide derivatives of III. 

This procedure, which is based on the work of Ishii and co-workers, affords a mild and general method for converting a wide variety of esters to primary, secondary, and tertiary amides (Table 1). While the preparation of the tertiary amide, N,N-dimethylcyclohexanecarboxamide, described here is carried out in benzene, aluminum amides derived from ammonia and a variety of primary amines have been prepared by reaction with trimethylaluminum in dichloromethane and utilized for aminolysis in this solvent. Although 1 equivalent of the dimethylaluminum amides from amines was generally sufficient for high conversion within 5-48 hours, best results were obtained when 2 equivalents of the aluminum reagent from ammonia was used. Diethyl-aluminum amides can also effect aminolysis, but with considerably slower rates. 

Organic derivatives of ammonia are called amines. Because nitrogen is trivalent, amines can be primary (attached to one carbon), secondary (attached to two carbons), or tertiary. All amines are basic, and their strength as bases increases with the number of alkyl groups attached to the nitrogen that is, methyl amine is a stronger base than ammonia and trimethylamine is stronger than dimethylamine. Amines can be prepared from ammonia and an alkyl halide ... 

Besides water, the most common weak base is ammonia, NH3, whose proton transfer equilibrium with water appears in Section 16-. Many other weak bases are derivatives of ammonia called amines, hi these organic compounds, one, two, or three of the N—H bonds in ammonia have been replaced with N—C bonds. The nitrogen atom in an amine, like its counterpart in ammonia, has a lone pair of electrons that can form a bond to a proton. Water does not protonate an amine to an appreciable extent, so all amines are weak bases. Table 17-4 lists several examples of bases derived from ammonia. 

---