Ammonium polysulfide preparation

Willgerodt reaction. In its original form this reaction involved heating an aryl alkyl ketone in a sealed tube at 210-230° with an aqueous solution of yellow ammonium polysulfide, prepared by dissolving sulfur in ammonium sulfide solution. The product is an aryl substituted aliphatic aciil amide, together with some of the corresponding carboxylic acid and often the hydrocarbon. An example is the... 

Polythiodipropionic acids and their esters are prepared from acryUc acid or an acrylate with sulfur, hydrogen sulfide, and ammonium polysulfide (32). These polythio compounds are converted to the dithio analogs by reaction with an inorganic sulfite or cyanide. 

Agrochemical Products. Hydrazones of vanillin have been shown to have a herbicidal action similar to that of 2,4-D, and the zinc salts of dithiovanillic acid. Made by the reaction of vanillin and ammonium polysulfide in alcohoHc hydrochloric acid, dithiovanillic acid is a vulcanization inhibitor. 5-Hydroxymerciirivanillin, 5- a cetoxym erci iri va n ill in, and 5-ch1oromercurivani11in have been prepared and found to have disinfectant properties. 

Compared with the huge number of oxo complexes only a few rhenium(V) compound with terminal sulfldo complexes are known. The square-pyramidal complex anion [ReS(S4)2] was first isolated in pure form in 1986 by a reaction of Rc207 with (Ph4P)Br and ammonium polysulfide in acetonitrile and the structure of the Ph4P+ salt has been elucidated. Later, the same complex anion was prepared from starting materials such as [Re2Cl8] , perrhenate, ... 

The corresponding 4-ethoxy derivative (m.p. 114°) was similarly prepared. When a yellow ammonium polysulfide solution was used, an anhydride with five sulfur atoms in the molecule was isolated4. 

A slurry of 0.50g (l.SOmmol) of Ti(MeCp)2Cl2 in lOmL of acetone is prepared in an open 2S-mL Erlenmever flask with magnetic stirring. In one portion, 1 mL of freshly filtered ammonium polysulfide solution is added to the Ti(MeCp)2Cl2 solution. After stirring for 15 min, the solution is filtered in air, and the red crystals are washed with water, methanol, and then two 5-mL portions of CS2. Yield 0.510 g (77%). 

Cyclooctasulfur exists as three main crystalline forms (allotropes) the most stable allotrope at 25°C is orthorhombic sulfur (Sa) (m.p. 112.8°C), found as large yellow crystals in volcanic deposits. When Sa is heated slowly to 95.5°C, it is converted to the high temperature monoclinic form (Sp) (m.p. 119.5°C), which also contains S8 rings but differently arranged. Another monoclinic form of sulfur (Sy) (m.p. 106.8°C) can be prepared by the slow crystallisation of sulfur from ammonium polysulfide. When sulfur... 

From most solvents Ss crystallizes as orthorhombic a-Ss. Monoclinic pSg is stable above 96 °C and is usually obtained by cooling liquid sulfur slowly below the triple-point temperature of 115 °C. At 25 crystals of pSg convert to polycrystalline a-Ss in less than 1 h but are stable for several weeks at temperatures below -20 C [27]. y-S is metastable at all temperatmes and occasionally crystallizes by chance, for example from ethanolic solutions of ammonium polysulfide [28], by decomposition of copper ethybcanthate [29] or in the preparation of bis(dialkylthiophosphoryl)disulfane [30]. Smpris-ingly, y-Ss occurs also naturally as the minerd rosickyite. Fmthermore, 7-8 is a component of stretched plastic sulfur which is obtained by quenching liquid sulfur from 350 C to 20 °C (in cold water) and stretching the fibers obtained in the direction of their axes. According to an X-ray diffraction study, this fibrous sulfur consists of helical polymeric sulfur chains (S[Pg.7]

An ammonium polysulfide solution is prepared as in Section 3-A above to this solution is added 3.00 g K2PdCl4 (9.18 mmole) dissolved in 10 mL water. After shaking for 2 minutes, the initial black precipitate redissolves, and the solution is filtered through diatomaceous earth (filter aid or Celite) prewashed with ammonium hydroxide. The filtrate is stoppered and the reaction allowed to proceed 5 days at room temperature (ca. 22°). At this time, the solution is noticeably lighter in color and the product has precipitated. After filtration, the complex is washed with water, ethanol, diethyl ether, carbon disulfide, and... 

Molybdenum and tungsten powders with average particle size 10-20/pm (99.99%) have been used in these procedures. Such powders are generally free of oxide forms, but if old samples are used, they should be heated in a stream of H2 (1000°C, 1 h) prior to use. Commercially available 99.5% liquid bromine is recommended to avoid the need to remove H2O. Commercial 20% ammonium polysulfide (NH4)2Sy can be used, or alternatively solutions can be prepared by passing H2S through a suspension of sulfur (15 g) in 25% aqueous NH3 (110 mL) until complete dissolution of the sulfur occurs. White crystalline 98.5%... 

The procedure of Muller and Krickemeyer also can be used for the preparation of (NH4)2[Mo3Si3] 2H2O by heating ammonium paramolybdate, (NH4)6 [M07O24] -4H20, in an aqueous solution of ammonium polysulfide in air. 

The reagent is prepared by wanning a light yellow solution of ammonium polysulfide with excess of powdered tellurium and filtering. Insoluble arsenites as well as AsgOs behave like alkali arsenites. (Idn. Limit 100 y Na AsOj). 

The reagent is prepared by warming yellow ammonium polysulfide with excess NaaSOs. Thioacetamide can also be used as a donor of S- ions. Alkali plumbites must be absent. 

Phenylacetamide from Acetophenone (Use of Ammonium Polysulfide) An ammonium sulfide Elution is prepared by passing hydrogen sulfide into concentrated aqueous ammonia until the solution is saturated. A mixture of 2 g. of acetophenone with 10 g. of the colorless ammonium sulfide solution and 1 g. of sulfur is heated in a closed tube for four hours at 200-220°. After the reaction mixture has cooled, it is treated with sufficient hydrochloric acid to decompose the ammonium... 

The Willgerodt reaction is useful in the preparation of arylacetic acids and amides from substituted methyl aryl ketones or vinyl aromatic compounds. The aliphatics and acetylenes give lower yields. The conversion is effected by heating aromatic compounds at 160°-200°C in an aqueous solution under pressure using ammonium polysulfide. In the Kindler modification, the ketone or styrene is refluxed with a mixture of sulfur and an amine, usually morpholine, to give a thioamide, ArCHjCSNRj. 

Polysulfides have been prepared with many different types of cations, both monoatomic Hke alkah metal ions and polyatomic Hke ammonium or substituted ammonium or phosphonium ions. In this chapter only those salts will be discussed in detail which contain univalent main-group cations although a large number of transition metal polysulfido complexes have been prepared [7-9]. 

Chemistry of Polysulfide Polymers. Propellant chemistry based on chemically crosslinked binders had its beginning at the Jet Propulsion Laboratory in the winter of 1946 when potassium and/or ammonium perchlorate were mixed into Thiokol LP-3 polysulfide liquid polymer, to which had been added an oxidative curative, p-quinone dioxime. This polysulfide polymer, as described by Jorczak and Fettes (13), is prepared... 

The ammonium polysulftde solution is prepared by adding I2g of elemental sulfur to 40g of 20% amonium sulfide (Alfa). The deep red solution is stirred for 10 h. Undissolved sulfur is not filtered, so that the polysulfide solution remains saturated. The solution is filtered prior to use. 

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