Ammonia initial report

A large volume expansion for solutions of sodium in ammonia was first reported by Kraus and Lucasse (17). Since this initial report, many investigations have been made of the volume expansion for a number of alkali metal-ammonia solutions. The techniques employed in these investigations have varied from density measurements for concentrated solutions using the Westphal Balance or Pycnometer to dilatometric studies for dilute solutions, which measure the volume expansion directly. 

Higginson and Wooding 277) also reported a transfer reaction to solvent for the case of the polymerization styrene in ammonia initiated by potassium amide. There was no termination event in their kinetic scheme, i.e., active center deactivation via a spontaneous termination event was not considered to be a significant event. 

Of the several routes to ethyleneurea, explored in 1941 at the request of the National Defense Research Committee1 and summarized briefly in the initial report of this work,2 those based on ethylene glycol and urea (or carbon dioxide and ammonia) or ethanolamine and urea are the subject of this paper. 

Reduction of pseudoephedrine amides with metal amide-borane complexes, and lithium amidotrihydroborate (LAB) in particular, furnishes the corresponding primary alcohols in high yield. In the initial report, LAB was prepared by deprotonation of the commercial, solid reagent borane-ammonia complex, using slightly less than 1 equiv of butyllithium as base (eq 11). In... 

Lewis base adducts of thorium(IV) and uranium(IV) aryloxides are readily prepared. Initial reports of phenoxide compounds of uranium(IV) describe NH3 derivatives from the reaction of UCI4 or UOCI2 with appropriate phenols in the presence of ammonia " (see Equations (15) to (17)) ... 

Amide ions have been used for many years to induce proton abstraction reactions and therefore might be expected to react with the tetramethylammonium ion in a similar way. In 1935, the decomposition of tetramethylammonium amide in liquid ammonia was initially reported by Franklin 44> to give trimethylamine and methylamine but no experimental details were given. Later, Hazlehurst, Holliday, and Pass 63> repeated Franklin s experiment 44> and noted that a trace of ethylene was evolved. During later attempts to prepare solid tetramethylammonium amide, a... 

The initial report of this remarkable reaction was followed by descriptions of a wide range of oxide-based photocatalysts for ammonia photosynthesis (Section II.B) that were said to function under a variety of experimental conditions. Studies on sulfides and other systems not based on oxides have also been reported (Section II.C). In particular, we note that the majority of the reports after Schrauzer describe the photosynthesis of ammonia in bulk liquid water, as shown in reaction 2. 

Schrauzer and Guth reported experiments in which they investigated a number of variables, including reaction time, temperature, pressure of N2 (up to 1.5 atm), sample pretreatment and storage, and nature of the radiation source. The reported ammonia photosynthesis was found to be remarkably tolerant of experimental procedure ammonia was detected after experiments performed in air, with normal sunlight, and in reaction vessels made of glass and not quartz. In no experiment described in the initial report, however, was more than 6.95 /unol of ammonia found. 

Despite many studies there is available, at this time, no unequivocal report of artificial photocatalytic synthesis of ammonia from nitrogen and water on heterogeneous catalysts. The chemical reaction 1, shown at the beginning of this chapter, remains speculative 17 years after it was initially reported. No rational start has yet been made on determining a mechanism for the reported nitrogen fixation process, despite the fact that a clear demonstration and understanding of any such process would be of great importance. Despite 17 years of research, the reported yields of ammonia from artificial photosynthesis remain at or near the limits of detection by routine analytical methods. As we stated earlier in this chapter, the concept of a major discovery that remains forever on the borderline of detectability is internally contradictory. The current state of the field is one where serious scientific skepticism is appropriate. 

Subsequent to the initial report of enhanced vapor transport of [Ba(tmhd)2]x by addition of NH3 to the carrier gas, it was discovered that an isolable compound is formed between these two species (equation 40). The X-ray diffraction crystal structure of [Ba(tmhd)2(NH3)2]2 indicated it to be a highly symmetric dimer (Figure 10). The localized geometry around the eight-coordinate barium atoms is nearly perfectly square-antiprismatic. The coordinated ammonia is not retained upon vapor transport. Thus, in all probability, it is the primary purpose of the added NH3(g) to break up [Ba(tmhd)2]x from the solid and transport it as [Ba(tmhd)2(NH3)2]2, or some other comparably lowered nuclearity species, in the vapor phase. 

One of the first anionic reactions studied in detail was the polymerization of styrene in liquid ammonia, with potassium amide as initiator, reported by Higginson and Wooding (1952). The reaction scheme proposed for this contains no formal termination step, and if all the impurities that are liable to react with the carbanions are excluded from the system, propagation should continue until all monomer has bear consumed, leaving the carbanion intact and still active. This means that if more monomer could be introduced, the active end would continue growing unless inadvertently terminated. These active polycarbanions were first referred to as living polymers by Szwarc (1968). 

This reaction was initially reported by Dutt, Whitehead, and Wormall in 1921. It is the preparation of aromatic azide via the basic hydrolysis of aromatic diazoaminosulfinate that can be easily synthesized from aromatic diazonium salt and arylsulfonamide or alkyl-sulfonamide. Therefore, this reaction is known as the Dutt-Wormall reaction. Similarly, azides can be prepared via the cleavage of compounds from diazonium salt with ammonia, hydrazine," hydroxylamine, etc. 

This reaction was initially reported by Favorskii in 1905 and subsequently extended by Babayan in 1939. It is a base-promoted or -catalyzed ethynylation of aldehydes and ketones to produce secondary or tertiary acetylenic alcohols or glycols using anhydrous KOH or NaOH. Therefore, it is generally known as the Favorskii-Babayan reaction or Favorskii reaction. Although it has been proposed that this reaction might involve a reaction between acetylene and the adduct from the ketone and KOH or a coupling of potassium acetylide with the carbonyl compounds, the most recent experimental results indicate that potassium hydroxide and acetylene first form a complex, rather than potassium acetylide in liquid ammonia, which then reacts with carbonyl compounds to form the acetylenic alcohols, where ammonia functions as a co-catalyst. The experimental evidence includes... 

This reaction was initially reported by Granacher in 1922. It is the preparation of thionic acid by the treatment of Aldol Condensation product from an aldehyde and rhodanine with a base (e.g., NaOH). Therefore, this reaction is known as the Granacher synthesis or Granacher reaction." The prepared thionic acid in this reaction can be further converted into a variety of derivatives under different conditions. For example, it can be transformed into a-thiol acid under a basic sodium amalgam reduction, whereas aliphatic acid is formed under an acidic zinc amalgam reduction. In addition, when the thionic acid is treated with ammonia, a-keto acid is generated, and the thionic acid can be converted into af-carboxyl oxime in reaction with hydroxylamine, from which either cy-amino acid or aliphatic nitrile forms via the treatment of sodium amalgam reduction or acetic anhydride, respectively. 

L-Phenylalanine, a precursor for coumarin (1) in Melilotus alba, is first converted to -cinnamic acid by the action of phenylalanine ammonia lyase (PAL) and then to ortho-coumaric acid (9) by the action of cinnamic acid >-hydroxyl-ase (Fig. 9.2). Although this step of the pathway was initially reported to occur in the chloroplast, at present none of the steps of the reaction sequence appear to occur there. Coum-aric acid (9) is converted into the corresponding 3-glucoside (10) by UDP-glucose and an 0-glucosyltransferase. This... 

Bossert and co-workers original three-component Hantzsch synthesis of nifedipine used 1 equiv of 2-ntirobenzaldehyde 181, 2 equiv of methyl acetoacetate 180, and ammonia to give nifedipine in 72% yield. Since their report, a number of variations on the Hantzsch 1,4-dihydropyridine synthesis have been reported. Many of the initial reports on the synthesis of 1,4-dihydropyridine derivatives were aimed at studying the structure activity relationships of these compounds with the goal of developing more potent and specific analogs of nifedipine. 

Sheratte55 reported the decomposition of polyurethane foams by an initial reaction with ammonia or an amine such as diethylene triamine (at 200°C) or ethanolamine (at 120°C) and reacting the resulting product containing a mixture of polyols, ureas, and amines with an alkylene oxide such as ethylene or propylene oxide at temperatures in the range of 120-140°C to convert the amines to polyols. The polyols obtained could be converted to new rigid foams by reaction with the appropriate diisocyanates. 

Reaction of perthiophosphonic anhydrides (64) with amines leads first to (105) and then, by further attack, to (106). With ammonia itself the second addition proceeds at the same phosphorus atom as the initial attack, giving (107) and (108). The anhydride (64) is also reported to react with 1,3-dioIs to give cyclic phosphonyl disulphides (109). Thermal decomposition of phenylphosphinic anhydride (110) may lead to the formation of PhP since in the presence of benzil the formation of the phosphorane (111) was observed. ... 

Denitrification can be affected by free ammonia, but this inhibition does not appear up to 300 to 400 mg/L NH3.46 This high concentration can justify that no inhibition of the denitrification process has been reported for this kind of wastewater.3-4 Eiroa and colleagues37 observed that nitrate was eliminated much faster at higher initial urea concentrations. However, they also found an increase of nitrite accumulation, which was later removed, due to high urea concentrations. 

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