Phosphorus and Sulfur Derivatives

Keywords. Phosphorus and sulfur derivatives, Dithioesters, Hetero Diels-Alder, Sigmatropic rearrangements. Chiral ligands... 

The carbon conient of steels usually dues ntn exceed 1,7 >. In addition to carbon, j lmn einhon. steels contain small amounts of silicon, manganese, phosphorus, and sulfur derived from Ihe raw materials and fuel used in the steelmaking process. Within limitations, silicon and manganese are beneficial anti often are purposely added, mainly because they are dcoxidants. Except in free-cutting steels, where sulfur is purposely added, sulfur and phosphorus are deleterious and their content is kept as low as... 

Ease of substitution. The carbonyl groups in iron pentacarbonyl may be substituted readily with numerous other ligands, such as unsaturated hydrocarbons, isocyanides, and certain phosphorus and sulfur derivatives. No analogous substitution reactions may be carried out with the [Mn(CO)s] anion. The substituted anion [Mn(CO)4P(C6Hs)3] , although preparable by other methods (48, 49), cannot be obtained by the action of triphenyl-phosphine on salts of the [Mn(CO)5] anion. 

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