Phosphorus trisulfide

Phosphorus trlsulfide can be synthesized either by Stock s method (I), which involves fusing red P and S and carefully purifying the crude product by recrystalllzatlon from CS3, followed by a second recrystalllzatlon from benzene, or according to German patent 309,618 (F. C. Frary), which uses white P in a high-melting inert solvent (II). 

The starting materials and the solvents must be carefully purified prior to use. Very pure crystalline S is powdered as finely 

An intimate mixture of 155 g. of red P and 96 g. of S is prepared and portions (40-50 g.) are reacted in a large diameter open test tube under a stream of dry CO 3. It is recommended that a pan filled with sand be placed under the test tube since the molten mass will immediately catch fire if the tube breaks. The test tube is first lightly preheated over its entire length to about 100°C and is then heated with a small flame in one spot at the upper edge of the mixture until the onset of the reaction. As soon as the entire charge has reacted (thereby becoming molten), it is heated to the point where distillation begins and then cool in a stream of CO3. The cake is then pulverized and extracted with hot CS3 (200 g. for each 100 g. of material). By evaporation of the CS3, an almost theoretical yield of crude sulfide, which melts between 130 and 150°C, is obtained. 

White P is dissolved in (virtually nonflammable) a-chloro-naphthalene and the stoichiometric quantity of S is added. The solvent acts as a diluent controlling the rate of reaction and causes crystallization of the sulfide. When the reaction is complete, the mixture is cooled with stirring. Most oftheP Sg precipitates as a fine powder. 

Yellowish-green, long rhombic needles stable in the air. M.p. 172.5°C, b.p. 407°C d ° 2.03. In the absence of O3 and moisture, remains stable above 700°C. Decomposed by water at elevated temperatures, evolving HgS. Soluble in CSg and benzene. These solutions become turbid in air almost immediately and gradually deposit a copious, yellowish-white precipitate. 

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Although phosphorus trisulfide (P4S6—but see below) and phosphorus pentasulfide (P4S10) have been widely used in the preparation of heterocyclic compounds there is no recent review. Weintraub has given an account of solvent- and temperature-dependent reactions of the pentasulfide, the compound employed in almost all recently reported work.118... 

ALKYLHALOPHOSPHINES, ALKYLPHOSPHINES tert-BUTYL PEROXOPHOSPHATE ESTERS iV-CHLORINATED PHOSPHORUS AMIDES HALOPHOSPHINES, METAL PHOSPHINATES METAL PHOSPHORUS TRISULFIDES NON-METAL OXIDES, NON-METAL SULFIDES PHOSPHINES, PHOSPHORUS ESTERS... 

See also ALKANETHIOLS, ALKENEBIS(SULFONIUM PERCHLORATES) allyl trifluo-ROMETHANESULFONATES, ARENEDIAZO ARYL SULFIDES BIS(ARENEDIAZO) sulfides, BIS(SULFURDIIMIDES DIAZONIUM SULFATES, DIAZONIUM SULFIDES AND DERIVATIVES METAL AMIDOSULFATES, METAL PHOSPHORUS TRISULFIDES METAL SULFATES, METAL SULFIDES, NON-METAL SULFIDES SULFONIC ACID ESTERS, SULFUR BLACK, SULFUR ESTERS THIOPHENOXIDES, XANTHATES ... 

White phosphorus reacts with sulfur on warming forming phosphorus trisulfide ... 

Phosphorus heptasulfide was obtained from the Oldbury Electrochemical Company. It has been shown 2 that the phosphorus trisulfide used by earlier workers for such fusions was actually somewhat impure phosphorus heptasulfide. 

Methylthiophene has been prepared by the dry fusion of a salt of methylsuccinic acid and phosphorus trisulfide. 4 This reaction was later investigated quite completely in respect to ratio of reactants, rate of heating, carbon dioxide atmosphere, and dilution of reactants with sand.6 An excellent technical method for preparing methylthiophenes has been described which involves a vapor-phase reaction of preheated sulfur with pentanes.6 3-Methylthiophene has also been prepared by adding 50% crude isoprene (amylenes) to molten sulfur at 350°.7... 

In a 3-I. round-bottom flask is placed an intimate mixture of 486 g. (3 moles) of finely powdered anhydrous sodium succinate (Note 1) and 648 g. (4.x moles) of finely ground phosphorus trisulfide (Note 2). The flask is fitted to a xoo-cm. (40-in.) condenser set for distillation (Note 3), and a tube for introduction of carbon dioxide is extended through the stopper to the center of the flask. The condenser is connected to a 2-1. flask cooled in an ice-salt mixture. The uncondensed gases are bubbled through two 2-1. flasks connected in series with the receiving flask each flask is cooled by an ice-salt mixture and contains 1 kg. of cracked ice and 200 cc. of 40 per cent sodium hydroxide. 

The first synthesis of thieno[2,3-6]thiophene (7) was reported in 1886, by the reaction of citric acid and phosphorus trisulfide, although the product was formed in only 1% yield (Scheme 105). The yield was subsequently improved to 10% (76AHC(19)123). Vapor phase reaction of acetylene and sulfur at high temperatures is also reported to produce (7), along with many other products. 

Substituted hexynediols such as (309) reacted with sulfur/phosphorus trisulfide to yield thieno[3,2-6]thiophene derivative (310 Scheme 106). The reactions described above, however, are not of practical use (76AHC(19)123). 

Methyl 2-thienyl sulfide has been prepared by the action of phosphorus trisulfide on dimethyl succinate 3 and by the action... 

Metal cyanides(and cyano complexes), 216 Metal derivatives of organofluorine compounds, 217 IV-Metal derivatives, 218 Metal dusts, 220 Metal fires, 222 Metal fulminates, 222 Metal halides, 222 Metal—halocarbon incidents, 225 Metal halogenates, 226 Metal hydrazides, 226 Metal hydrides, 226 Metal hypochlorites, 228 Metallurgical sample preparation, 228 Metal nitrates, 229 Metal nitrites, 231 Metal nitrophenoxides, 232 Metal non-metallides, 232 Metal oxalates, 233 Metal oxides, 234 Metal oxohalogenates, 236 Metal oxometallates, 236 Metal oxonon-metallates, 237 Metal perchlorates, 238 Metal peroxides, 239 Metal peroxomolybdates, 240 Metal phosphinates, 240 Metal phosphorus trisulfides, 240 Metal picramates, 241 Metal pnictides, 241 Metal polyhalohalogenates, 241 Metal pyruvate nitrophenylhydrazones, 241 Metals, 242 Metal salicylates, 243 Metal salts, 243 Metal sulfates, 244 Metal sulfides, 244 Metal thiocyanates, 246 Metathesis reactions, 246 Microwave oven heating, 246 Mild steel, 247 Milk powder, 248... 

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