Ammonium sulfide, reducing agent

This is by far the most important reaction of tetrazolium salts and accounts for the bulk of their many applications. A large variety of reagents can reduce tetrazolium salts, e.g., 53 to formazans, e.g., 51. Ascorbic acid, hydrazine, and hydroxylamine have been recommended for the preparation of formazans from tetrazolium salts.245 Stronger reducing agents such as ammonium sulfide, sodium amalgam, sodium dithionite, and catalytic hydrogenation can further reduce the formazans to the amidrazones, e.g.,... 

One of the nitro groups of 92 is readily reduced when it is slurried in aqueous ammonium chloride with sodium sulfide monahydrate as the reducing agent, and 2,3,5-triamino-6-nitropyrazine (93) is produced in high yield (74USP3808209). 

Reducing agents commonly employed are iron, tin, or SnCI2 in hydrochloric acid and ammonium or alkali-metal sulfides catalytic hydrogenation and electrolytic reduction also are employed (see Section 23-12B). 

Partial reduction of aromatic polynitro compounds leads to nitro amines. The most successful reagents are the alkali metal or ammonium sulfides in aqueous alcoholIn some instances, sodium bicarbonate combined with sodium sulfide gives better results because of the formation of sodium hydrosulfide, which is believed to be the main reducing agent. Also, aqueous methanol is preferred to aqueous ethanol. Nitro compounds that are sparingly soluble in alcohol solutions may be reduced by hydrogen sulfide in pyridine solution. ... 

About the same time, Zinin, N. (1812-1880) was able, in 1842, to carry out an original synthesis of aniline, that he named benzidam, and of some other aromatic amines by reduction reaction of nitrobenzenes. As for a reducing agent, Zinin utilized a solution of ammonium sulfide to generate molecular hydrogen14,15. 

AMATOL (8006-19-7) A shock- and heat-sensitive explosive mixture of ammonium nitrate (NH4NO3) and trinitrotoluene (C7H5N3O6) that may decompose violently if struck or heated. Either component may react violently (possible detonation) with oxidizers, reducing agents, amines, strong bases, caustics. Incompatible with hydrides, nitrides, sulfides sodium hydroxide potassium hydroxide. 

AMMONIUM MONOSULFIDE (12124-99-1) NH4 HS (aqueous) (NH4)2S (anhydrous) The anhydrous material is pyrophoric in air it decomposes at room temperature, releasing ammonia and toxic and flammable hydrogen sulfide gas. Stable below 32°F/0°C. The commercial product [a 40% solution in water (NH4HS)] is stable. The aqueous solution is a reducing agent. Violent reaction with strong oxidizers... 

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