Ammonia formaldehyde

From ammonia, formaldehyde and formic acid. Sommelet and Ferrand, Bull. soc. chim. (4) 35, 446 (1924). (This method has been checked by one of the editors and is highly recommended.)... 

Hexamine Ammonia, Formaldehyde Used to make C4-like compounds... 

The trimethylamine may be generated by the action of alkali on trimethylamine hydrochloride and dissolved in acetone. The submitter prepared trimethylamine by the method of Som-melet and Ferrand and obtained a 65% yield by the interaction of ammonia, formaldehyde, and formic acid. The checkers found that a commercial 25% solution of trimethylamine in methanol (210 ml.) gave the same yields as the acetone solution. 

These molecules are flexible because rotation about single bonds is free, so they can wrap themselves around a metal ion to obtain four comfortable donor-atom-to-metal links within five-membered rings. Nitrilotriacetic acid is easily synthesized industrially from ammonia, formaldehyde, and hydrocyanic acid (the Strecker synthesis) and therefore is potentially an inexpensive but effective chelating agent. 

Hexamethylenediamine peroxide is practically insoluble in water and in the majority of organic solvents. According to Taylor and Rinkenbach [90] it is volatile at a temperature higher than room temperature and at 75°C it decomposes markedly losing methylamine. At 100°C it is totally decomposed after 24 hr. When boiled in water it decomposes, and passes into solution with evolution of oxygen, the aqueous solution contains ammonia, formaldehyde, ethylene glycol, formic acid and hexamethylenetetramine. 

Anodic oxidation of 6- and 7-pteridone, using electrolysis at a controlled potential, gave pteridine-6,7-dione in 95-100% yield.409 Under controlled-potential electrolysis conditions pteridine-6,7-dione is oxidized to the bridgehead diol, which undergoes rearrangement, further oxidation, and hydrolysis, yielding tetraketopiperazine, oxamide, urea, oxamic acid, ammonia, formaldehyde, formic acid, and C02-... 

When hexamethylenetriperoxidediamine is boiled with water, it disappears fairly rapidly, oxygen is given off, and the colorless solution is found to contain ammonia, formaldehyde, ethylene glycol, formic acid, and hexamethylenetetramine. 

Methenamine (Hiprex, Mandelamine, Urex) exerts antibacterial properties in a unique fashion. In an acidic environment, this drug decomposes into formaldehyde and ammonia. Formaldehyde is bactericidal to almost all bacteria, and bacteria do not develop resistance to this toxin. This mechanism enables methenamine to be especially useful in treating urinary tract infections, because the presence of this drug in acidic urine facilitates the release of formaldehyde at the site of infection (i.e., within the urinary tract). Use of methenamine is safe, although high doses are associated with gastrointestinal upset and problems with urination (bloody urine, pain while urinating). 

The most important reaction examples for the formation of IVW-acetals involve formaldehyde because it tends more than most other carbonyl compounds to undergo additions (Section 9.1.1). With ammonia formaldehyde gives hexamethylenetetramine (Figure 9.24). This compound contains six lYW-acetal subunits. 

The ammonia-formaldehyde reaction is highly exothermic. Therefore the reactor is operated under a vacuum so that the heat of reaction can be used to evaporate some of the water of reaction. This helps concentrate and crystallize the hexamine in the water solution. If dry solids are desired, the hexamine-water solution is pumped through a crystals receiver and then separated in a centrifuge. The crystals pass through a rotary dryer and are packaged for shipment. In some cases a liquid solution may be shipped to customers125. 

Masella M, Flament J-P (1999) A theoretical study of five water/ammonia/formaldehyde cyclic trimers Influence of cooperative effects. J Chem Phys 110 7245-7255... 

Haldor Topsoe A/S Ammonia Formaldehyde Methanol HYDRO Olefins IFP... 

Unknown Methanol, acetone, diethylether, acetonitrile, acetic acid, HCl, ammonia, formaldehyde, diethylamine... 

An even better source for chemicals is your local piiar-macy. It would be best if it was one near a hospital, as they usually have more chemicals in stock, such as strong ammonia, formaldehyde, etc. 

The solubility of an inhaled contaminant influences the disposition of gases, vapors, and particulates. In general, those substances that are highly water soluble, such as ammonia, formaldehyde, and hydrogen chloride, will be removed by the upper respiratory tract. Formaldehyde is concentrated in the nasal mucosa and is a nasal carcinogen in the rat. Chemicals with intermediate solubility, such as halogens and ozone, deposit in both the upper respiratory tract and the lung, while chemicals with low... 

Clearly the ammonia-formaldehyde reaction competes with the process but, using an excess of these reagents, the condensation can be made almost quantitative with respect to the tris(ethylene-diamine) complex. The specificity is decided by the chirality of the parent tris(ethylenediamine) complex since this decides the orientation of the gem-diamine and subsequent additions of the amino group to the adjacent imine. Unless the gem-diamine is oriented in the apical position, condensation to give the cap is prohibited. The A or A configuration of the ethylenediamine chelates then decides the orientation of the secondary proton if the amino methylene moiety is required to be apical A(S) or A(R). 

Needless to say, we have only touched on a few of the many analytical procedures involving air samples. Other analyses performed include the determination of acetylene, total aldehydes, ammonia, formaldehyde, formic acid, and total organic acids. Various aerosol fractions in the air are commonly analyzed. 

The novel 1,3,5,7-tetraazabicyclo[3.3.1]nonanes (138) were prepared by the reaction of diazonium salts with either hexamine or an aqueous mixture of ammonia-formaldehyde (Scheme 220). 

Hot-box emissions The patterns are generally heated by open air gas burners, producing combustion gas emissions. The off-gas may contain phenol, ammonia, formaldehyde and monoisocyanates (if the resin contains nitrogen)... 

The explosive hexogen (RDX) is produced according to the SH process. Hexamine is nitrated with an excess of 8-10 times of concentrated nitric acid (98.5 %). The reaction temperature should not exceed 23 °C in order to avoid runaway. Apart from the reacting substances and the product ammonia, formaldehyde and other materials are present in the reactor. The reaction is exothermic and the mixture is chemically unstable. Hence, the reaction temperature and the excess of nitric acid have to be kept within the permissible range in order to avoid an explosion. The reaction takes place in the nitrator whose P l diagram is shown in Fig. 4.11. It represents the first part of a cascade of reactors where the reaction is completed and the product is conditioned. The process is continuous and the process stream progresses from reactor to reactor by overflow. 

The world setting for chemistry has continued to change. The center of chemical activity has moved from Africa to India to Asia to Arabia to Europe to North America—if a center, that is, still exists. Chemistry has become increasingly delocalized and is now better described as a global enterprise. There have also been major technical advances affecting the course of chemistry—computers, transistors, lasers, space travel—and these have opened completely new areas of study. With such probes as Voyager we learned of planets with seas of hydrocarbons and bedrock of water and ammonia ice. Spectroscopists have found evidence of molecules in the empty space between stars, including carbon monoxide, ammonia, formaldehyde, cyanoacetylene, acetaldehyde, methyl mer-... 

Figure 14.3 Flow diagram of gas-phase reaction to produce pyridine and 3-methylpyridine from ammonia, formaldehyde and acetaldehyde...

Roundup , manufactured by Monsanto (USA), is one of the most widely used herbicides in the world. A key intermediate for its manufacture is disodium iminodiacetate (DSIDA), which is traditionally made through Strecker s process. This process requires the use of ammonia, formaldehyde, and hydrogen cyanide. Hydrogen cyanide is extremely toxic, and its use requires special handling to minimize risk to workers, the community, and the environment. Ammonia and formaldehyde are also associated with human health problems and environmental hazards. The process produces 1kg waste for every 7 kg product. The waste contains cyanide and formaldehyde, which need to be treated prior to safe disposal. 

If one wishes to stndy a reaction theoretically, the most simple example is usually where one starts, which wonld be with the ammonia/formaldehyde reaction in the present case. Bnt when stndying a reaction experimentally, it is often convenient to start with much more complicated examples. The latter approach was followed historically, and we will discnss it here in historical order. 

Figure 9.7. Effect of basis set superposition error (BSSE) correction on the ab initio energy profile for the ammonia-formaldehyde pair." ...

Figure 9.8. Comparison of the MM40 energies without the Lewis bonding parameters, with the BSSE corrected ab initio energies for the ammonia—formaldehyde pair. ...

By eliminating the need for hydrogen cyanide, ammonia, formaldehyde, and hydrochloric acid, this new method for production of... 

It seems to me that once we accept the above, we are back to a situation where the only feature that distinguishes self-assembly or self-organization from any run-of-the-mill synthetic reaction, which also proceeds spontaneously given a suitable set of conditions, will be the requirement diat three or more constituent molecules are being assembled. Thus, the old Hantsch synthesis of pyridines from ammonia, formaldehyde, and a ketone, the preparation of sugar mixtures from formaldehyde and base, and all polymerizations will become examples of self-assembly. 

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