abstract |
Dialkylphosphine is added to a mixture of sulfur and water at 50 DEG -90 DEG C. After approximately 25% of the dialkylphosphine is charged, an alkali, such a sodium hydroxide, is added to neutralize the dialkyldithiophosphinic acid that forms. At this elevated temperature the neutralization reaction proceeds rapidly thereby preventing any alkali from reacting with the sulfur to form sulfides. Dialkyldithiophosphinate yields from this process are on the order of about 95-98%. |