Subject monosulfides

CASRN 12427-38-2 molecular formula C4ff6MnN2S4 FW 265.31 Chemical/Physical. When soil containing maneb was subjected to a stream of moist air, carbon disulfide was formed. Carbon disulfide was also formed when maneb was suspended in a O.IM phosphate buffer at pff 7.0 and air was drawn through the system. The rate of carbon disulfide was higher at neutral and acidic solutions but lower under alkaline conditions. When the air was replaced by nitrogen, no carbon disulfide was evolved. Decomposition products in the reaction vessel identified by TLC were ethylene thiourea, ethylene thiuram monosulfide, elemental sulfur, and trace amounts of ethylenediamine (ffylin, 1973). 

Maneb or mancozeb. Maneb released to water may be subject to abiotic degradation to ethylene thiuram disulfide, ethylene thiourea (ETU), ethylenediamine (EDA), and ethylene thiuram monosulfide (ETM)... 

Pyrolytic conversion of 6 to 7 with extrusion of sulfur is a slow reaction which apparently involves in the latter stages an unusual attack of thiyl radical on carbon to form the monosulfide structure. Pyrolysis of 8 to 7, also demonstrated separately, is a more direct example of conversion of a fluoroalkyl disulfide to monosulfide by intramolecular attack of thiyl radical on carbon. The dithiane 7, once formed, is stable at 300°C, indicating that the CF2--S bond in these compounds is not subject to homolysis. The related formation of an acyclic monosulfide—e.g., CF3SCF3—from an acyclic disulfide—e.g., CF3SSCF3— requires photochemical activation or temperatures higher than 300°C. 

Polymers containing a monosulfide linkage in both the main chain and the pendent group are the subject of many detailed stndies. A few reviews of the synthesis and properties of all types of polymers have been pnbhshed (1-4) the nearest one covering polymer with sulfiir in the main chain appeared in 1992 (3). Polysulfides with controlled and well-defined structures are easily prepared. 

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