Phosphorous pentasulfide

By reacting phosphorous pentasulfide with dioxo derivatives of tetrahydro-l,3-oxazine, the oxygen atoms of both carbonyl groups are replaced by sulfur (27) ... 

The complex thioamide lolrestat (8) is an inhibitor of aldose reductase. This enzyme catalyzes the reduction of glucose to sorbitol. The enzyme is not very active, but in diabetic individuals where blood glucose levels can. spike to quite high levels in tissues where insulin is not required for glucose uptake (nerve, kidney, retina and lens) sorbitol is formed by the action of aldose reductase and contributes to diabetic complications very prominent among which are eye problems (diabetic retinopathy). Tolrestat is intended for oral administration to prevent this. One of its syntheses proceeds by conversion of 6-methoxy-5-(trifluoroniethyl)naphthalene-l-carboxyl-ic acid (6) to its acid chloride followed by carboxamide formation (7) with methyl N-methyl sarcosinate. Reaction of amide 7 with phosphorous pentasulfide produces the methyl ester thioamide which, on treatment with KOH, hydrolyzes to tolrestat (8) 2[. 

Sulfur can replace 30-50% of the asphalt in the hlends used for road construction. Road surfaces made from asphalt-sulfur hlends have nearly double the strength of conventional pavement, and it has been claimed that such roads are more resistant to climatic conditions. The impregnation of concrete with molten sulfur is another potential large sulfur use. Concretes impregnated with sulfur have better tensile strength and corrosion resistance than conventional concretes. Sulfur is also used to produce phosphorous pentasulfide, a precursor for zinc dithiophosphates used as corrosion inhibitors. 

Spiroindolinobenzothiopyrans can be prepared by condensation of Fischer s base with thiosalicylaldehyde derivatives 46 in ethanol, as shown in Scheme 22.71,89 93 Reaction of 1,2,3,3-tetramethylindolinium salt with carbamoylthiobenzaldehyde,92 which is an intermediate for preparation of thiosalicylaldehyde, also gives the spirobenzothiopyran in high yield via the corresponding indolinium salt, as shown in Scheme 22.94 Conversion of spirobenzopyrans to the corresponding spirobenzothiopyran by phosphorous pentasulfide in pyridine or xylene is possible, but the purification of the product is difficult. 

The classic syntheses of the antibacterial sulfonamides involve reaction of the appropriate arylamine with an acid addition salt of p-amino-benzenesulfonyl chloride, or p-nitrobenzenesulfonyl chloride followed by reduction. Chemical interest largely resides in preparation of the corresponding arylamines. For the synthesis of sulfacytine (134), N-ethyl uracil (131) was converted to its thioamide (132) by reaction with phosphorous pentasulfide. The newly introduced sulfur is then displaced with ammonia in methanol to give 133. Standard reactions complete... 

The Paal-Knorr Thiophene Synthesis allows the generation of thiophenes by condensation of a 1,4-dicarbonyl compound in the presence of an excess of a source of sulfur such as phosphorous pentasulfide or Lawesson s reagent. 

N-((Benzyl)oxy)carbonyl)-L-phenylalaninal Phosphorous pentasulfide Vanadium(III) chloride Ethyl chloroacetate a-Acetoxyisobutyryl bromide Thioformamide... 

To a cooled (0°C) solution of formamide (30.5 mL, 0.76 mol) in 1 L of diethyl ether was added 89 g (0.19 mol) of phosphorous pentasulfide in small portions with stirring. The reaction mixture was allowed to warm to ambient temperature, stirred for 2 h, filtered, and concentrated in vacuo to afford thioformamide as a yellow offensive smelling oil which was used without purification. 

The phosphorochloridothioate is obtained from phosphorous pentasulfide as follows ... 

In one example, phosphorous pentasulfide was used in conjunction with a thiol to... 

The 2-carbonyl group of benzodiazepin-2-ones can be converted into the thione using traditional reagents such as phosphorous pentasulfide <82CPBil4i> or Lawesson s reagent <90JMC450>. A new reagent prepared from phosphorous pentasulfide and four equivalents of an alkyllithium smoothly converts lactams into thiolactams in THF solution. Thus, desmethyldiazepam (35) is converted into... 

Phosphorus sulfides as P4S10, dimeric form of phosphorous pentasulfide... 

Lin Z, liu Z, Fu W, Dudney NJ, Liang C (2013) Phosphorous pentasulfide as a novel additive for high-ptaformance lithium-sulfur batteries. Adv Funct Matra 23 1064—1069... 

Phosphorous PentasuLfide. Phosphorous pentasulfide (P2S5) has been described as an electrolyte additive for high-energy lithium-sulfur batteries (70). P2S5 passivates the surface of metallic lithium anodes, promotes the dissolution of Li2S, blocks the polysulfide shuttle, and thus enables a long battery cycle life. 

A three neck round bottomed flask was equipped with a dropping funnel, water cooled condenser, argon purge, electric heating mantle and magnetic stirrer. The flask was charged with 1,2 di (p-n-butylphenyl)ethane 1,2 dione(1.8 g, 3.6 mmol), phosphorous pentasulfide (1.2 g 5., 5 mmol) and 30 dioxane. The mixture was refluxed for 5 hours. The reaction mixture was filtered hot to remove the unreacted phosphorous pentasulfide and the residue was washed with hot dioxane several times. The filtrate was returned to the cleaned round bottom flask, and nickel (ll)chloride hexahydrate (0.48 g, 2.0 mmol) in 10 ml of water was... 

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