Organosulfur compounds, applications

Other Rhodococcus strains similar to those described above in terms of the desulfurization ability have also been isolated [83], The purpose of identifying such Rhodococcus strains, in several cases, appears to be the development of in-house biocatalysts for BDS application. The specificity of the desulfurizing strains of organosulfur compounds in addition to DBT has also been studied (Table 3). 

Organosulfur chemistry is presently a particularly dynamic subject area. The stereochemical aspects of this field are surveyed by M. Mikojajczyk and J. Drabowicz. in the fifth chapter, entitled Qural Organosulfur Compounds. The synthesis, resolution, and application of a wide range of chiral sulfur compounds are described as are the determination of absolute configuration and of enantiomeric purity of these substances. A discussion of the dynamic stereochemistry of chiral sulfur compounds including racemization processes follows. Finally, nucleophilic substitution on and reaction of such compounds with electrophiles, their use in asymmetric synthesis, and asymmetric induction in the transfer of chirality from sulfur to other centers is discussed in a chapter that should be of interest to chemists in several disciplines, in particular synthetic and natural product chemistry. 

Some organosulfur compounds can function as fuel antioxidants by acting to decompose hydroperoxides. Organosulfides are believed to react with hydroperoxides to form sulfoxides. The sulfoxides then further react with hydroperoxides to form other more acidic compounds. These newly formed acids continue the process of decomposing and reaction with hydroperoxides. Thus, organosulfur compounds function in the process oxidation inhibition through hydroperoxide decomposition. However, in most fuel applications, sulfur-containing antioxidants are not utilized. 

Whitehurst, Isoda, and Mochida write about catalytic hydrodesulfurization of fossil fuels, one of the important applications of catalysis for environmental protection. They focus on the relatively unreactive substituted di-benzothiophenes, the most difficult to convert organosulfur compounds, which now must be removed if fuels are to meet the stringent emerging standards for sulfur content. On the basis of an in-depth examination of the reaction networks, kinetics, and mechanisms of hydrodesulfurization of these compounds, the authors draw conclusions that are important for catalyst and process design. 

Organosulfur Compounds. These compounds, listed in Table 8, are used in a variety of applications, including cooling water, paint, and metalworking. Methylenebisthiocyanate hydrolyzes rapidly at a pH above 8 to cyanate ion which complexes with ferric iron to poison the cytochrome systems (36). 

Carbon disulfide (CS2) is one of the most significant sulfur compounds because of its widespread use and toxicity. This compound has two sulfur atoms, each separately bonded to a carbon atom. This compound is a volatile, colorless liquid (mp, -111°C bp, 46°C). Unlike most organosulfur compounds, it is virtually free of odor. Although its uses are declining, it has numerous applications in chemical synthesis, as a solvent to break down cellulose in viscose rayon manufacture, and in the manufacture of cellophane. It has also been used as an insecticide and fumigant. 

Acetic anhydride is a useful solvent in certain nitrations, acetylation of amines and organosulfur compounds for rubber processing, and in pesticides. Though acetic acid is unexceptional as a fungicide, small percentages of anhydride in acetic acid, or in cold water solutions are powerful fungicides and bactericides. There are no reports of tliis application in commerce. It is possible that anhydride may replace formaldehyde for certain mycocidal applications. 

A number of synthetic applications of different classes of organosulfur compounds have already been mentioned in previous chapters. The purpose of this chapter is to highlight the major organosulfur reagents, giving their important uses in synthetic organic chemistry. 

Mikolajczyk, M., Grzejszczak, S., Chefezynska, A., and Zatorski, A., Addition of elemental sulfur to phosphonate carbanions and its application for the synthesis of a-phosphoryl organosulfur compounds. Synthesis of aromatic ketones, J. Org. Chem., 44, 2967, 1979. 

Organosulfur compounds have been widely investigated among compounds of interest for the formation of self-assembled monolayers on gold [57]. The latter are relevant for a number of applications such as biosensing, nanopatterning and molecular electronic devices. The study of fundamental processes in the formation of SAMNs of organosulfur compounds is of primary importance to realize functional molecular layers. 

Evans, Jr., S. A. Oxygen-17 and Sulfur-33 Nuclear Magnetic Resonance Spectroscopy of Organosulfur Compounds, in Magnetic Resonance. Introduction, Advanced Topics and Applications to Fossil Energy, Petrakis, L., Frassard, J. P. (eds.), Reidel Dordrecht, 1984. Fiat, D. Bull. Magn. Res. 6 (1984) 30. 

Organic Synthesis Procedures Featuring the Synthesis of Organosulfur Compounds and Preparative Applications thereof,... 

Chemical and Agrochemical Applications Mohsin [263] developed an IC-MS method using thermospray and electrospray interfaces for the analysis of organophosphorus and organosulfur compounds in an insecticide such as monomethyl phosphate, monomethyl sulfate, and dimethyl phosphate. All three compounds were separated on an lonPac ASH anion exchanger using a NaOH/ methanol mixture as an eluent. Mohsin used an Alltech lOOOHP suppressor to convert the eluent to water prior to entering the MS interface. The Alltech lOOOHP suppressor contains two packed-bed suppressor columns. One of the... 

Stanescu MA, Ginosar DM, Bala GA, Anderson RP. Biocatalytic treatment of organosulfur compounds in emulsions in supercritical fluids. Fuel Chem Div Preprints 2002 47 524-6. Ginosar DM, Bala GA, Anderson RP, Fox SL, Stanescu MA. Bioprocessing of high sulfur crudes via application of critical fluid biocatalysis. Bechtel Bwxt Idaho Idaho National Engineering and Environmental Laboratoy 2002. LLC lNEEL/EXT-02-00711. 

Jayne, D., Zhang, Y, Haij, S. and Erkey, C. (2005) Dynamics of removal of organosulfur compounds from diesel by adsorption on carbon aerogels for fuel cell applications. Int. J. Hydrogen Energ., 30, 1287-1293. 

Organosulfur compounds are mainly slimiddes with little application in plastics. The trichloromethyl thiophthalimides are used as fungicides in PVC. 

A number of organosulfur and organophosphorus compounds have been synthesized for various purposes including pesticidal applications. A common class of organosulfur compounds consists of thiols, the simplest of which is methanethiol ... 

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