Ammonia as reducing agent

Birch reduction 1,4-Reduction of aromatic rings using alkali metals dissolved in liquid ammonia as reducing agents. 60... 

Due to the higher basicity of the medium, isomerization at the more labile asymmetric centers may occur, a shortcoming that is usually avoided with lithium/ammonia as reducing agent, and also by lanthanides (Section 2.3.2.6). 

With the selective catalytic reduction process by using ammonia as reducing agent, NOx emission can be reduced under diesel engine exhaust gas conditions... 

The flue gas produced in the boiler of a power plant is passed to the SCR reactor together with ammonia as reducing agent (Figure 6.18.11). The main reactions of catalytic NO, reduction are described by ... 

Solutions of alkali metals in liquid ammonia are used in organic chemistry as reducing agents. The deep blue solutions effectively contain solvated electrons (p. 126), for example... 

Dialkyl and diaryl ditellurium compounds are easily reduced to tellurols and tellurolates. Alkali metals in liquid ammonia or in an inert organic solvent, sodium borohydride in methanol, ethanol, alcohol/benzene, THF, DMF, or in a basic aqueous medium, lithium aluminum hydride in dioxane or THF/hexamethylphosphoric triamide, and thiourea dioxide in THF/50% aqueous sodium hydroxide have been used as reducing agents (p. 164). The tellurolates are easily oxidized in air. For this reason they are almost always used in situ. 

Leuckart-Wallach reaction. Reductive alkylation of ammonia or of primary or secondary amines with carbonyl compounds and formic acid or formamides as reducing agents. 

There have been numerous reports on the reduction of activated cyclopropanes with alkali metals either dissolved in liquid ammonia or used in suspension. Most of these reactions were carried out with lithium as reducing agent. In an early study, various substituted cyclopropyl ketones were treated with lithium in liquid ammonia. rranj-l-Acetyl-2-methylcyclopropane (1, R = Me = H R = Me) gave 3,4,4-trimethyl-2-pentanone (3) as the result of... 

The Leuckart-Wallach reaction992 consists of the reductive alkylation of ammonia or an amine by a carbonyl compound with formic acid or a derivative thereof as reducing agent ... 

The catalytic reduction of nitrogen oxides, NO, that are produced by combustion of fuels at high temperatures (=1800°C during electric power generation) is one of the important environmental catalytic problems. Review the process that uses ammonia or small hydrocarbons as reducing agents, and list the catalysts that are employed [204, 205]. 

In certain cases, alkanolamines function as reducing agents. For example, monoethanolamine reduces anthraquinone to anthranols, acetone to 2-propanol, and azobenzene to aniline (17). The reduction reaction depends on the decomposition of the alkanolamine into ammonia and an aldehyde. Similarly, diethanolamine converts o-chloronitrobenzene to 2,2 -dichloroazobenzene and w-dinitrobenzene to 3,3 -diaminoazobenzene. 

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