Phosphorotrithioite

Phosphorotrithioite, 21 61 Phosphorus, 33 106-107 acids, pK values of, 3 383 bond angles in trihalides, 13 365 bromochlorides, 7 12 bromofluorides, 7 8-9, 10 chalcogenide halides, 23 400 chloFofluorides, 7 8, 9-10 complexes, xenon fluoride reactions, 46 86 compounds... 

The best known of these defoliants are sodium chlorate which has the danger of starting fires, tributyl-phosphorotrithioite (merphos, Folex) its oxygenated relative tributylphosphorotri-thioite (DEF), and endothall (Accelerate). Recent research reports claim that amino methyl phosphonic acid and certain of its relatives were found to be more active than current commercial products. The best known desiccant used for defoliation of cotton is paraquat (1,1 -dimethyl-4,4 -bipyridinium) (8). 

Many trivaient phosphorus compounds, trialkyl phosphites and trialkyl phosphorotrithioite exhibit fungicidal properties, mainly because of their considerable reducing effect and high reactivity (Nishizawa et al., 1959). These compounds are also very phytotoxic, and are therefore used mainly as defoliants, for example, merphos and tributyl phosphorotrithioite. 

TRIBUTYL PHOSPHOROTRITHIOITE (C4H3S)3P FROM ELEMENTAL PHOSPHORUS... 

Functionalized phosphonodithioic derivatives have been obtained by well established reactions which include, for example, the formation of 5,5-dialkyl [(a-thioureido) benzyljphosphonodithioates from trialkyl phosphorotrithioites, aromatic aldehydes and a thiourea (equation 31), a reaction that parallels the formation of the phosphonic analogues... 

Methyl phosphorodichloridite Dimethyl phosphorochloridite Trimethyl phosphite Trimethyl phosphorotrithioite Hexamethylphosphorous triamide Methyl tetramethylphosphorodiamidite Dimethyl dimethylphosphoramidite Methyl diethylphosphoramidochloridite 0-Methyl S.S-diethyl phosphorodithioite Ethylphosphonous acid Ethylphosphonous dichloride Methyl ethylphosphonochloridite Dimethyl ethylphosphonite 0-Methyl S-phenyl ethylphosphonothioite Dibutyl phosphonite ... 

In order of greatest to least effect the following compounds cause delayed neurotoxicity Phosphonates, phosphorofluoridates, phosphonofluorldates, phosphorodiamidofluoridates, phosphoroamidofluoridates, phosphates, phos-phorotrithioates, phosphorotrithioites, and phosphites. 

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