Dimethyl dithiophosphoric acid is the organophosphorus compound with the formula (CH3O)2PS2H. It is the processor for production of the organothiophosphate insecticide Malathion. Although samples can appear dark, the compound is a colorless, distillable liquid.J. Svara, N. Weferling, T. Hofmann "Phosphorus Compounds, Organic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2006.
It is prepared by treating phosphorus pentasulfide with methanol: Lefferts, J. L.; Molloy, K. C.; Zuckerman, J. J.; Haiduc, I.; Guta, C.; Ruse, D., "Oxy and thio phosphorus acid derivatives of tin. 1. Triorganotin(IV) dithiophosphate esters", Inorganic Chemistry 1980, volume 19, 1662-1670. P2S5 + 4 CH3OH → 2 (CH3O)2PS2H + H2S
See also Ammonium diethyl dithiophosphate Diethyl dithiophosphoric acid Zinc dithiophosphate
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