Formate ammonium, with

The conversion of an aldehyde or ketone into the corresponding amine by heating with ammonium formate or with formamide and formic acid at about... 

Another method of preparation involving methyl formate has been reported whereia the formate reacts with ammonia and methanol ia the presence of ammonium chloride at 255°C and 2.9 MPa (28.6 atm) (15). In this case, monomethylformamide is present ia considerable quantities as a by-product. 

Many of these salts melt or sublime before or during decomposition and reaction temperatures generally increase with molar mass. Thermal analyses for a selection of ammonium carboxylates have been given by Erdey et al. [915] who conclude that the base strength of the anion increases with temperature until it reaches that of NH3. Decompositions of ammonium acetate (>333 K) and ammonium oxalate (>473 K) proceed through amide formation. Ammonium benzoate and ammonium salicylate sublime (>373 K) without decomposition but ammonium citrate decomposes (>423 K) to yield some residual carbon. 

Rubia tinctorum roots Alizarin, alizarin glucoside, purpurin, pseudopurpurin, lucidin glucoside, lucidin primeveroside, munjistin, ruberythric acid EtOH/H20, H2S04 A ACN B ammonium formate/FA with EDTA 250, 254 nm/ESI (+) Post column modification of eluent (5% NH3 in H20) for NI mode... 

The addition of buffering salts to the mobile phase often improves chromatographic separation, provides a stable pH during separation, and reduces problems associated with column disturbances produced by highly variable samples. These salts are usually volatile (examples are ammonium formate, ammonium acetate, and i-ethylammonium hydroxide) and the concentrations used are usually less than 10 mM. With the advent of orthogonal interfaces for ESI and APCI, the absolute requirement for volatile salts has disappeared. However, the prolonged use of nonvolatile salts is not recommended as the accumulation of salts in the spray chamber of the MS reduces sensitivity and increases maintenance requirements. 

Sulphur is soluble in solutions of the sulphides of the alkali metals, including ammonium, with the formation of yellow solutions of polysulphides.6 The alkali carbonates and the hydroxides of the alkali and alkaline earth metals, in aqueous solution, also dissolve sulphur, producing sulphides or polysulphidcs together with thiosulphates and sulphites. In all probability the ideal equation for hydroxides is ... 

Chloramines were analysed in additional experiments by selective spectrophotomet-rical procedure (HACH method 10171). When the chloride concentration is nearly zero, de facto no chlorine or chloramines (measured as the difference between total and active chlorine) are visible. Ammonium is formed linearly in the cathodic reaction (A). In the second case B, active chlorine is consumed by the ammonium with chloramine formation. After switching off the electrolytic current, this reaction continues until all the chlorine is reacted. 

Macroscopic solvent effects can be described by the dielectric constant of a medium, whereas the effects of polarization, induced dipoles, and specific solvation are examples of microscopic solvent effects. Carbenium ions are very strong electrophiles that interact reversibly with several components of the reaction mixture in addition to undergoing initiation, propagation, transfer, and termination. These interactions may be relatively weak as in dispersive interactions, which last less than it takes for a bond vibration (<10 14 sec), and are thus considered to involve "sticky collisions. Stronger interactions lead to long-lived intermediates and/or complex formation, often with a change of hybridization. For example, onium ions are formed with -donors. Even stable trityl ions react very rapidly with amines to form ammonium ions [41], and with water, alcohol, ethers, and esters to form oxonium ions. Onium ion formation is reversible, with the equilibrium constant depending on the nucleophile, cation, solvent, and temperature (cf., Section IV.C.3). 

Many water-insoluble ketones, aliphatic, aryl aliphatic, and heterocyclic, respond favorably to treatment with ammonium formate or formamide to form with subsequent hydrolysis the primary amines. A typical procedure for the synthesis of a-phenylethylamine (66%) from acetophenone and ammonium formate has been applied to many other ketones (65-84%). Nuclear alkoxyl, halo, and nitro groups are not disturbed. The reaction with formamide as the reducing agent is catalyzed by ammonium formate, ammonium sulfate, or magnesium chloride. ... 

Catalyzed reductions with ammonium formate proceed with retention of configuration, at least for the case of nitro compounds. Treatment of steroid derivative (12) with ammonium formate in methanolic solution and a catalytic amount of palladium on charcoal gave exclusively amino steroid (13), as shown in equation (13). A similar technique has been used to produce members of the ephedrine family. 

Fig. 2.1. Nucleotide fractionation. A sample of p2 phage RNA uniformly labelled with and the pyrimidines labelled with was digested with alkali ( 2.1.1) and separated by column chromatography on Dowex 50 formate eluted with 0.25 M ammonium formate pH 4.1. The ultraviolet transmission graph is traced from the record of a Uvicord I ultraviolet monitor output Radioactivities were measured by dissolving the samples in a scintillation cocktail and counting in a liquid scintillation counter. The peaks were identified from their ultraviolet spectra.

CARBAMALDEHYDE (75-12-7) Combustible liquid (flash point 310°F/154°C oc). Reacts slowly with water, forming hydrocyanic acid and ammonium formate. Incompatible with strong acids, alkali metal acetates, ammonia, cellulose acetate, cresols, isocyanates, metal chlorides, oleum, phenols, polyvinyl alcohol,... 

The main issue with atmospheric pressure sources is efficient sampling of the molecular ion species which must be transferred from normal atmospheric pres-siue to a vacuum chamber. This is effected by passing the ion stream through a pin hole and a series of focusing lenses into a two-stage pumped separator which removes the bulk of the neutral molecules. However, the nature of this transfer process makes the inlet prone to contamination, and the use of inorganic and non-volatile buffers in the HPLC separation will rapidly block these systems. Volatile buffers, such as ammonium formate, ammonium acetate and small concentrations of trifluoroacetic acid are best suited for LC/MS procedures. 

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