Tetramethyldiphosphine disulfide

Tetramethyldiphosphine disulfide (46.5 g., 0.25 mole) and 111 g. (0.50 mole plus 10% excess) of tributylphosphine are added directly to the three-necked flask. The funnel is replaced with a... 

Tetraethyl- and tetramethyldiphosphine disulfide (Orgmet, Inc., 300 Neck Rd. Haverhill, Mass. 01830), tributylphosphine (Carlisle Chemical Works, Inc., Reading, Ohio 45215), and 1,3-dichloropropane (Eastman Kodak Company, Rochester, N.Y. 14600) were obtained commercially and used without further purification. The first two reactants are completely inert to one another at room temperature and can be placed in the reaction vessel simultaneously. 

Dimethylthiophosphinic bromide has been prepared by addition of elemental bromine to tetramethyldiphosphine disulfide suspended in carbon tetrachloride.1- The reaction is rather general in that alkyl or aryl groups other than methyl can be attached to the phosphorus atom to give products of the type... 

III) fluoride or by fluorination of the complex [(CH3)2-PCl2][AlCl4], formed by reaction of methyldichlorophos-phine, methyl chloride, and aluminum chloride with hydrogen fluoride. The compound is also formed upon reaction of tetramethyldiphosphine disulfide with antimony (III) fluoride.The latter procedure, which could be applied to synthesize numerous other trifluorophos-phoranes, is described below. 

The distillation flask is charged udth 49.0 g. (0.26 mole) of tetramethyldiphosphine disulfide and 10.3 g. (0.27 mole) of lithium hydroaluminate, and the flask is flushed with nitrogen. Four hundred milliliters of anhydrous dioxane (distilled from sodium) is added all at once through the addition funnel. The distillation column is adjusted to provide total reflux of the dimethylphosphine, and the reaction mixture is stirred for 4 hours. Moderately rapid hydrogen evolution occurs, and the... 

Phosphorus chemical shift and spin-spin coupling P-P tensors have been determined by Gee et al for tetramethyldiphosphine disulfide. 

The reaction flask is charged under nitrogen with 15.0 g (80mmole) tetramethyldiphosphine disulfide,6 32.3 g (39.0 mL, 160mmole) tributylphosphine, and 1.44 g (80 mmole) distilled water. The mixture is heated to 160-170° under stirring. When the mixture has become homogeneous, the temperature of the oil... 

The yield of dimethylphosphine can be increased by increasing the amount of tributylphosphine which allows use of water in the less volatile form of a hydrate. Thus using the same apparatus, procedure and with the same amount of tetramethyldiphosphine disulfide, using 50.5 g (250mmole) P(n-C4H9)3 and 15.2 g (80mmole) p-toluenesulfonic acid hydrate, the yield of dimethylphosphine is 7.1 g (95%). 

Infrared and Raman spectral analyses of tetramethyldiphosphine disulfide have been interpreted in terms of opposed phosphorus-sulfur... 

The drying of impure ethers can produce a violent explosion. Further information about this hazard may be found in Inorganic Syntheses, Volume 12, p. 317. A hazard associated with the synthesis of tetramethyldiphosphine disulfide [ Inorg. Synth., 15, 186 (1974)] is cited in Inorganic Syntheses, Volume 23, p. 199. 

A reaction which is formally the reverse of this decomposition occurs when tetramethyldiarsine and tetramethyldiphosphine disulfide are heated 316a). 

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